Magnetic field or radiation oscillating at several frequencies for improving efficacy and/or reducing toxicity of magnetic hyperthermia

ABSTRACT

Magnetic nanoparticles for use in a magnetic hyperthermia therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis method, wherein the magnetic nanoparticles are administered to a body part of an individual and the body part is exposed to a magnetic field or radiation oscillating at a high frequency and at a medium and/or low frequency, wherein the high frequency is 1 MHz at the most, the medium frequency is lower than the high frequency, and the low frequency is lower than the high frequency and lower than the medium frequency when it is present.

CROSS-REFERENCE

This application is a continuation-in-part of U.S. patent application Ser. No. 16/325,486, filed on February 14, 2019, which is a National Stage Application of International Application PCT/IB2018/000218, filed on Dec. 12, 2012, which claims priority to EP Application 17290023, filed on Feb. 16, 2017, the entire contents of which are hereby incorporated by reference.

FIELD

The invention relates to the use of a magnetic field, oscillating at several frequencies, to improve the efficacy and to decrease the toxicity of a treatment by magnetic hyperthermia.

BACKGROUND

Magnetic hyperthermia is a method in which nanoparticles are heated under the application of an oscillating magnetic field. Such method can be used as a treatment, for example when magnetic nanoparticles are introduced in or sent to tumors and heated under the application of an oscillating magnetic field, leading to antitumor efficacy. One way to achieve high efficacy of such treatment is to use nanoparticles with a high heating power or a large specific absorption rate (SAR), where the SAR is usually measured in Watt per gram of nanoparticle.

Various studies introduce nanomaterials with high SAR. However, there appears to be a limit on the maximum achievable SAR. Concerning the most commonly used nanoparticles for magnetic hyperthermia, i.e. iron oxide nanoparticles, it has been suggested to increase their size to increase their SAR. This has in particular been made possible by using magnetosomes, which are iron oxide nanoparticles synthesized biologically by magnetotactic bacteria (Alphandery et al. (2011) ACS Nano, Vol. 5, P. 6279). Improvement in nanoparticle heating properties by increasing nanoparticle sizes is however limited since nanoparticles larger than 100 nm usually become multidomain and thus lose their magnetic properties. It has also been suggested to increase nanoparticle SAR by increasing nanoparticle magnetic anisotropy, but this has usually been achieved by using nanoparticles doped with toxic transition metals such as cobalt, which must be avoided for medical applications.

SUMMARY

In this invention, we introduce a new method to improve the efficacy of a magnetic hyperthermia treatment and to reduce its toxicity. This method consists in exposing magnetic nanoparticles contained in the tissue or organ to be treated, such as a tumor, to an oscillating magnetic field or radiation, which oscillates at two or more different frequencies. One frequency is preferentially called a high oscillation frequency. It preferentially lies between 10⁻³ kHz and 10⁶ kHz, or between 10⁻² kHz and 10⁵ kHz, or between 10⁻¹ kHz and 10⁴ kHz, or between 1 kHz and 10³ kHz, or between 50 kHz and 200 kHz, and is preferentially used to heat the magnetic nanoparticles. In some cases, the high frequency is lower than 10⁹, 10⁸, 10⁶, 10⁵, 10⁴, 10³, 10², 10, or 1 kHz. In some cases, the high frequency is larger than 10⁻⁹, 10⁻⁷, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 50, 100, or 1000 kHz. Another frequency is preferentially called a medium frequency. It preferentially lies between 0.5 Hz and 250 000 kHz, or between 5 Hz and 25000 kHz, or between 50 Hz and 250 kHz, or between 500 Hz and 25 kHz, and preferentially modulates the high frequency and/or preferentially enables to reach a higher or larger maximum magnetic field or radiation or a higher or larger high frequency of oscillation. In some cases, the medium frequency is lower than 10⁹, 10⁷, 10⁵, 10³, or 10 kHz. In some other cases, the medium frequency is larger than 10⁻⁵, 10⁻³, 10⁴, 1, 10, 100, 500, 10³, or 10⁴ Hz. Still another frequency is preferentially called a low frequency. It is preferentially between 10⁻⁹ Hz and 10³ Hz, or between 10⁻⁸ Hz and 10² Hz, or between 10⁻⁷ Hz and 10 Hz, or between 10⁻⁶ Hz and 1 Hz, or between 10⁻⁵ Hz and 1 Hz, or between 10⁻Hz and 1 Hz, or between 10⁻³ Hz and 1 Hz, or between 10⁻² Hz and 1 Hz, or between 10⁻⁴ Hz and 1 Hz. It is preferentially lower than 10³, 10², 10, 1, or 10⁻¹ Hz, and preferentially enables to induce heating and cooling steps. It is preferentially larger than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, or 1 Hz.

This method may be advantageous for the following reasons. First, it may increase treatment safety. On the one hand, it may limit Eddy or Foucault currents and therefore possible heating of the whole organism. On the other hand, with this method it may be possible to yield anti-tumor efficacy with temperatures reached during treatment, which may globally be lower than those reached with the application of a magnetic field or radiation oscillating at only one frequency. Second, it may increase treatment efficacy by enabling the application of a series of temperature gradients, or heating and cooling steps, which may be more efficient in destroying tumors than the application of a continuous magnetic field or radiation usually producing a more constant temperature. Third, with this method it may be possible to consider a treatment in which the strength or amplitude of the applied magnetic field or radiation, the number of heating and cooling steps, the heating and cooling times, are fixed depending on the temperature that one wants to achieve. Thus, on the one hand, it may not be necessary to vary the strength or amplitude of the magnetic field or radiation applied during treatment to reach a given temperature, as is usually the case in a magnetic hyperthermia treatment. On the other hand, it may be possible to suppress the use of a temperature probe during treatment by using a pre-calibration curve that determines the strength or amplitude of the magnetic field or radiation, as well as heating and cooling times, which must be used to produce heating and cooling steps. Fourth, treatment safety may also be strengthened since overheating may be reached more rarely with a magnetic field or radiation oscillating at more than one frequency than with that oscillating at only one frequency.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 : (a), for a magnetic field oscillating only at a high frequency, f_(h), variation of the magnitude of magnitude flux density with time, with indications of time t₁ during which the magnetic field amplitude increases, time t₂ during which the magnetic field amplitude decreases, time t₃ during which the magnetic field is constant, with indication of H_(max) corresponding to the maximum magnetic field amplitude among the different values of H_(max,i), where H_(max,i), corresponds to the local maximum of magnetic field amplitude at each high frequency oscillation. f_(h) may be equal or proportional to 1/[2(t₁+t₂+t₃)]. (b), for a magnetic field oscillating at a high frequency, f_(h), and a medium frequency, f_(m), which may be equal or proportional to 1/[(t₄+t₅+t₆)], variation of the magnitude of magnetic flux density with time, with indications of time t₄ during which the magnetic field amplitude increases, time t₅ during which the magnetic field amplitude decreases, time t₆ during which the magnetic field is constant, with indication of H_(max) corresponding to the maximum magnetic field amplitude among different values of H_(max,i), where H_(max,i) corresponds to the local maximum of magnetic field amplitude at each high frequency oscillation and H_(av) is equal or proportional to (Σ_(i=1) ^(i=n) Hmax, i)/n, where n is the number of high frequency oscillations.

FIG. 2 : (a), Percentage of H_(max) and H_(av) as a function of time following the switching on of coil 2 working with an alternating current I of 195 A. Similar curves were obtained for coil 1 at I equal to 50, 100, 150, 200, 250, 300, 350, 400 A, and for coil 2 at I equal to 50, 100, 150, 200, 250, 300, 350, 400, or 450 A, and for coil 3 at I equal to 25, 50, 100, 150, or 200 A, and for coil 4 at I equal to 25, 50, 100, 150, 200, or 250 A. (b), for a magnetic field oscillating at high, medium, and low frequency, variation of magnetic field amplitude as a function of time, showing the A₇ low frequency sequence, taking place during t₇ and corresponding to the heating step, followed by the A₈ low frequency sequence, taking place during t₈ and corresponding to the cooling step. f_(l) may be equal or proportional to 1/(t₇+t₈). (c), for a magnetic field oscillating at high, and low frequency, variation of magnetic field amplitude as a function of time, showing the A₉ low frequency sequence, taking place during t₉ and corresponding to the heating step, followed by the A₁₀ low frequency sequence, taking place during t₁₀ and corresponding to the cooling step. f_(l) may be equal or proportional to 1/(t₉+t₁₀).

FIG. 3 : (a), Variation of the magnetic flux density in axial direction as a function of time, showing both the high oscillation frequency, f_(h)=195 kHz, and the medium oscillation frequency, f_(m)=15 kHz. (b), Variation of the maximal flux density in the radial direction as a function of time, showing both the high oscillation frequency, f_(h)=195 kHz, and the medium oscillation frequency, f_(m)=15 kHz. (c), Magnitude of magnetic flux density as a function of time, showing both twice the high oscillation frequency, 2.f_(h)=390 kHz, and the medium oscillation frequency, f_(m)=15 kHz. H_(max) corresponds to the maximum value of the magnitude of magnetic flux density among the different values of H_(max,i), where H_(max,i) is the maximum magnitude of magnetic flux density estimated for each high frequency oscillation. H_(av) corresponds to the average value among all values of H_(max,i). The magnetic flux density, also designated as the strength of the magnetic field, is measured in the radial and axial direction of the cylindrical probe, where the probe is positioned so that its axial direction is parallel to the main magnetic field generated by coil 2. This is the reason why the strength of the magnetic field in the axial direction is much higher or larger than that in the radial direction. The magnitude of magnetic flux density is also designated as the amplitude of the magnetic field.

FIG. 4 : Positioning of the probe used to measure the strength or amplitude of the magnetic field in coil 2, as a function of the distance from the edge of coil 2, (0), measured in cm. (b), Measurement of H_(max) and H_(av) as a function of the distance, measured from the center of coil 2, using an alternating current of 500 A, where 1.5 cm corresponds to the center of the coil and 0 to the edge of the coil as indicated in (a).

FIG. 5 : Temperature variation as a function of time of a suspension of 100 μl of M-PLL, (a), or BNF-Starch, (b), at a concentration of 10 mg/mL, exposed to oscillating magnetic fields generated by coils 2 and 4 according to conditions (H_(av), H_(max), f_(m), f_(h)) mentioned in table 1.

FIG. 6 : (a), Temperature variation as a function of time of confluent GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, exposed during 30 minutes to a magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, of fixed H_(av)=61 mT and H_(max)=85 mT, (-●-), of H_(av)=49-61 mT and H_(max)=68-85 mT to reach 45° C.,(-▪-), of H_(av)=53-61 mT and H_(max)=75-85 mT to reach 50° C., (-♦-), of H_(av)=55-61 mT and H_(max)=77-85 mT to reach 55° C., (-▾-). In the control, confluent GL-261 cells were exposed to a magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, and of H_(av)=61 mT and H_(max)=85 mT. (b), Upper curve, temperature variation as a function of time of GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, exposed to sequences of application of the magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, H_(av)=61 mT and H_(max)=85 mT, corresponding to heating steps, followed by sequences of non-application of the magnetic field, corresponding to cooling steps. The heating times, t₇, correspond to those necessary to reach 45° C., while the cooling times, t₈, correspond to those necessary for the temperature to decrease from 45° C. to 35° C. In this case, the oscillating magnetic field oscillates at a low frequency of 1.6-2.5 10⁻³ Hz. Bottom curve, temperature variation as a function of time for GL-261 cells without BNF-Starch exposed to the same sequences of application and non-application of the magnetic field as for the upper curve. (c), Upper curve, temperature variation as a function of time of GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, exposed to sequences of application of the magnetic field, oscillating at f_(h)=196 kHz, f_(m)=15 kHz, H_(av)=61 mT and H_(max)=85 mT, corresponding to heating steps, followed by sequences of non-application of the magnetic field, corresponding to cooling steps. The heating times, t₇, correspond to those necessary to reach 50° C., while the cooling times, t₈, correspond to those necessary for the temperature to decrease from 50° C. to 37° C. In this case, the magnetic field oscillates at a low frequency of 1.2-1.7 10⁻³ Hz. Bottom curve, temperature variation as a function of time for GL-261 cells without BNF-Starch exposed to the same sequences of application and non-application of the magnetic field as for the upper curve. (d), Upper curve, temperature variation as a function of time for GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, exposed to sequences of application of the magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, H_(av)=61 mT and H_(max)=85 mT, corresponding to heating steps, followed by sequences of non-application of the magnetic field, corresponding to cooling steps. The heating times, t₇, correspond to those necessary to reach 55° C., while the cooling times, t₈, correspond to those necessary for the temperature to decrease from 55° C. to 37° C. In this case, the magnetic field oscillates at a low frequency of 0.9-1.1 10⁻³ Hz. Bottom curve, temperature variation as a function of time for GL-261 cells without BNF-Starch exposed to the same sequences of application and non-application of the magnetic field as for the upper curve.

FIG. 7 : (a), For the first hyperthermia session, temperature variation as a function of time of 25 μg in iron of BNF-Starch per mm³ of tumor introduced to GL-261 tumors and exposed continuously during 30 minutes to a magnetic field, oscillating at f_(h)=202 kHz and f_(m)=15 kHz, with H_(av)=27 mT and H_(max)=57 mT. 14 additional hyperthermia sessions during which a magnetic field, oscillating at f_(h)=202 kHz and f_(m)=15 kHz, with H_(av)=24-31 mT and H_(max)=54-67 mT, followed the first hyperthermia session. (b), For the first hyperthermia session, temperature variation as a function of time of 25 μg in iron of BNF-Starch per mm³ of tumor introduced to GL-261 tumors and exposed during 20 minutes to a magnetic field, oscillating at f_(h)=202 kHz, f_(m)=15 kHz, with H_(av)=11 mT and H_(max)=57 mT, applied during t₇, followed by non-application of the magnetic field during t₈. 20 hyperthermia sessions of 20 minutes each followed the first hyperthermia session, during which a magnetic field, oscillating at f_(h)=202 kHz, f_(m)=15 kHz and f_(l)=19 10⁻³ Hz was applied. The times t₇ and t₈ associated to heating and cooling steps of the different cycles are indicated in table 8. (c) Heating times t₇ as a function of the hyperthermia session. (d), Cooling times t₈ as a function of the hyperthermia session. (e), Low frequency of oscillation, f_(l)=[1/(t₇+t₈)], as a function of the hyperthermia session.

FIG. 8 : (a), Variation of the tumor volume as a function of time (days) following day 0, the day of BNF-Starch administration, where BNF-Starch are either administered without application of a magnetic field, (●), BNF-Starch are administered followed by 15 hyperthermia session (3 per week) during which a magnetic field oscillating at f_(h)=202 kHz and f_(m)=15 kHz with H_(av)=24-31 mT and H_(max)=54-67 mT is applied during 30 minutes, (A), BNF-Starch are administered followed by 21 hyperthermia sessions (3 per week) during which a magnetic field oscillating at f_(h)=202 kHz, f_(m)=15 kHz, f_(l)=4-25 mHz with H_(av)=7-23 mT and H_(max)=57 mT is applied during 20 minutes, (▾). (b), Mouse survival rate as a function of time (days) following day 0, the day of BNF-Starch administration, where BNF-Starch are either administered without application of a magnetic field, (●), BNF-Starch are administered followed by 15 hyperthermia session (3 per week) during which a magnetic field oscillating at f_(h)=202 kHz and f_(m)=15 kHz with H_(av)=24-31 mT and H_(max)=54-67 mT is applied during 30 minutes, (▴), BNF-Starch are administered followed by 21 hyperthermia sessions (3 per week) during which a magnetic field oscillating at f_(h)=202 kHz, f_(m)=15 kHz, f_(l)=4-25 mHz with H_(av)=7-23 mT and H_(max)=57 mT is applied during 20 minutes, (▾).

DETAILED DESCRIPTION

The invention relates to magnetic nanoparticles for use in a magnetic hyperthermia therapeutic treatment, prophylactic treatment or diagnosis method, wherein the magnetic nanoparticles are administered to a body part of an individual and the body part is exposed to a magnetic field or radiation oscillating at a high frequency and at a medium and/or low frequency.

In one embodiment of the invention, the body part is the body part of an individual, animal, or human.

In an embodiment of the invention, the body part comprises more than or at least 1, 2, 5, 10, or 100 similar or different organism(s), apparatus, organ(s), tissue(s), cell(s), or biomolecule(s).

In some cases, the body part can be all or part of the head, neck, shoulder, arm, leg, knee, foot, hand, ankle, elbow, trunk, inferior members, or superior members.

In some other cases, the body part can be or belong to an organ, the musculoskeletal, muscular, digestive, respiratory, urinary, female reproductive, male reproductive, circulatory, cardiovascular, endocrine, circulatory, lymphatic, nervous (peripheral or not), ventricular, enteric nervous, sensory, or integumentary system, reproductive organ (internal or external), sensory organ, endocrine glands. The organ or body part can be human skeleton, joints, ligaments, tendons, mouth, teeth, tongue, salivary glands, parotid glands, submandibular glands, sublingual glands, pharynx, esophagus, stomach, small intestine, duodenum, jejunum, ileum, large intestine, liver, gallbladder, mesentery, pancreas, nasal cavity, pharynx, larynx, trachea, bronchi, lungs, diaphragm, kidneys, ureters, bladder, urethra, ovaries, fallopian tubes, uterus, vagina, vulva, clitoris, placenta, testes, epididymis, vas deferens, seminal vesicles, prostate, bulbourethral glands, penis, scrotum, pituitary gland, pineal gland, thyroid gland, parathyroid glands, adrenal glands, pancreas, heart, arteries, veins, capillaries, lymphatic vessel, lymph node, bone marrow, thymus, spleen, gut-associated lymphoid tissue, tonsils, brain, cerebrum, cerebral hemispheres, diencephalon, brainstem, midbrain, pons, medulla, oblongata, cerebellum, spinal cord, choroid plexus, nerves, cranial nerves, spinal nerves, ganglia, eye, cornea, iris, ciliary body, lens, retina, ear, outer ear, earlobe, eardrum, middle ear, ossicles, inner ear, cochlea, vestibule of the ear, semicircular canals, olfactory epithelium, tongue, taste buds, mammary glands, or skin.

In some cases, the body part or organ can belong to the blood circulation or circulatory system.

In some cases, the body part can be or comprise at least one tumor, cancer, virus, bacterium, or pathological cell.

In one embodiment of the invention, the body part is or comprises water, an excipient, a solution, a suspension, at least one chemical element, organic material, or gel, which can be synthetic or produced by a living organism.

Preferably, the body part of an individual, also designated as the body part, represents or is part of an individual or a whole individual, where the individual is preferentially a human, an animal, or an organism, preferentially a living or inactivated or dead organism, comprising at least one prokaryotic or eukaryotic cell.

In one embodiment of the invention, the body part is alive (or not), is any tissue, water, medium, substance, cell, organelle, organ protein, lipid, DNA, RNA, biological material, preferentially localized in a specific region of an individual, preferentially originating or extracted from such region.

In an embodiment of the invention, the body part comprises a pathological site, a healthy site, and/or a nanoparticle or composition region.

In one embodiment of the invention, the body part is or comprises a pathological site or pathological cells.

In some cases, the pathological site can be defined as an unhealthy site, or a site that is in a different condition from a site of a healthy individual, or the site of an unhealthy individual. It can comprise pathological cells, such as tumor cells, bacteria, eukaryotic or prokaryotic cells, as well as viruses or other pathological material. Pathological cells can be cells that are: i) not arranged or working as they usual do in a healthy individual, ii) dividing more quickly than healthy cells, iii) healthy cells having undergone a transformation or modification, iv) dead, sometimes due to the presence of a virus or to other organisms, or v), in contact, in interaction, with foreign material not belonging to the individual, such as viruses, where viruses can possibly penetrate, colonize, or replicate in these cells. In some cases, pathological cells can be assimilated to viruses or to other organisms or entities that colonize cells or target cells or destroy cells or use cells or enter in interaction with cells, preferentially to enable their own reproduction, multiplication, survival, or death. In some cases, a pathological site can comprise healthy cells, preferentially with a lower number, activity or proliferation, than that of pathological cells.

In one embodiment of the invention, the body part is or comprises a healthy site or healthy cells. In some cases, the healthy site can be defined as a site or region that comprises healthy cell(s), where a healthy cell can be defined as a cell that belongs to a healthy individual or to the body part of a healthy individual.

In some cases, the healthy site can surround the pathological site when it is preferentially located at a distance of less than 1 or 10-9 m from the pathological site.

In some cases, the composition or body part can be exposed to radiation.

The invention also relates to magnetic nanoparticles for use in a magnetic hyperthermia therapeutic treatment, prophylactic treatment or diagnosis method, wherein the magnetic nanoparticles are administered to a body part of an individual and the body part is exposed to a magnetic field or radiation oscillating at a high frequency and at a medium and/or low frequency, wherein the high frequency is 1 MHz at the most, the medium frequency is lower than the high frequency, and the low frequency is lower than the high frequency and lower than the medium frequency when it is present.

In one embodiment of the invention, the individual is a human or an animal. In one embodiment of the invention, the high frequency is lower than 10⁶, 10³, 10, 1, 10⁻¹, 10³, 10⁻⁶, 10⁻⁹, 10⁻¹², or 10⁻¹⁵ MHz.

In one embodiment of the invention, the high frequency is lower than 10⁶, 10⁵, 10⁴, 10³, 500, 100, 50, 20, 10, 5, or 1 kHz.

In still another embodiment of the invention, the high frequency lies between 1 and 10⁹ kHz, or between 1 and 10⁶ kHz, or between 1 and 10³ kHz.

In another embodiment of the invention, the medium frequency is lower than the high frequency by a factor of at least 1.01, 1.1, 2, 5, 10, 10², 10³, 10⁵ or 10¹⁰. The ratio between f_(h) and f_(m), f_(h)/f_(m), can be larger than 1.01, 1.1, 2, 5, 10, 10², 10³, 10⁵ or 10¹⁰.

In still another embodiment of the invention, the low frequency is lower than the high frequency and medium frequency when it is present by a factor of at least 1.01, 1.1, 2, 5, 10, 10², 10³, 10⁵ or 10¹⁰. The ratio between f_(h) and f_(l), f_(h)/f_(l), or the ratio between f_(m) and f_(l), f_(m)/f_(l), can be larger than 1.01, 1.1, 2, 5, 10, 10², 10³, 10⁵ or 10¹⁰.

The present invention also relates to a magnetic hyperthermia prophylactic, therapeutic treatment or diagnosis method of an individual, comprising administering an effective amount of magnetic nanoparticles to a body part of the individual and exposing the body part to a magnetic field or radiation oscillating at a high frequency and at a medium and/or low frequency.

In one embodiment of the invention, a magnetic field or radiation oscillating at high and medium and/or low frequency is the same as a magnetic field or radiation oscillating at high, and medium and/or low frequency. It designates a magnetic field or radiation that oscillates at high and medium frequencies or a magnetic field or radiation that oscillates at high and low frequencies or a magnetic field or radiation that oscillated at high, medium, and low frequencies.

In one embodiment of the invention, the magnetic field or radiation can designate an oscillating magnetic field or radiation, also designated as alternating magnetic field or radiation, where the oscillating magnetic field or radiation can designate a magnetic field or radiation oscillating with time, preferentially at a low frequency, f_(l), and/or at a medium frequency, f_(m), and/or at a high frequency, f_(h), and/or at several frequencies, and/or at more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 50, or 100 frequencies. The variations of the amplitude of the magnetic field or radiation with time are represented in FIG. 1(a) for an oscillation at f_(h), in FIG. 1(b) for an oscillation at f_(m) and f_(h), in FIG. 2(b) for an oscillation at f_(m), f_(l), and f_(h), in FIG. 2(c) for an oscillation at f_(h) and f_(l).

In one embodiment of the invention, the magnetic field or radiation is applied during high frequency sequences of duration t_(i), t₂, or t₃ for oscillation at f_(h) (FIG. 1(a)), medium frequency sequences of duration t₄, t₅, or t₆ for oscillations at f_(h) and f_(m) (FIG. 1(b)), low frequency sequences of duration t₇, or t₈ for oscillations at f_(h), f_(m), and f_(l) (FIG. 2(b)), low frequency sequences of duration t₉, or t₁₀, for oscillations at f_(h) and f_(l) (FIG. 2(c)).

According to the invention, a frequency can be defined when a sequence is repeated at least 2, 3, 5, 10, 50, 100, 10³, 10⁵, or 10¹⁰ times, and preferentially when the durations of the different sequences associated with a given frequency vary by less than a factor of 1.1, 1.5, 2, 5, 10, 10², 10³, 10⁵, or 10¹⁰ between these different sequences, or preferentially when the durations of the different sequences associated with a given frequency vary by a factor comprised between 1.01 and 10¹⁰, or between 1.1 and 10⁷, or between 1.1 and 10⁵, or between 1.1 and 10³, or between 1.1 and 100, or between 1.1 and 10, or preferentially when the durations of the different sequences associated with a given frequency vary by factor of more than 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10³, 10⁵, or 10⁷.

According to the invention, a frequency can be measured by using the average values of t_(i), t₂, t₃, t₄, t₅, t₆, t₇, t₈, t₉, t₁₀, t₁₁, or t₁₂, also designated as t_(i) for 1<i<12. t, can be expressed using the relation: t_(i)=Σ_(j=1) ^(j=m) t_(i,j)/m where j represents any given sequence and m is the total number of sequences. Preferentially, m is larger than 2, 5, 10, 10³, or 10⁶. In some cases, m can be lower than 10⁶, 10⁵, 10⁴, 10³, 10², 10, 9, 8, 7, 6, 5, 4, 3, or 2. In some cases, m can be comprised between 2 and 10⁶, or between 2 and 10⁵, or between 2 and 10³, or between 2 and 10, or between 2 and 5, or between 2 and 4, or between 2 and 3, or between 3 and 4, or between 3 and 5, or between 3 and 10, or between 3 and 10², or between 3 and 10⁵, or between 3 and 10⁷. According to the invention, a sequence of duration t₁, t₂, t₃, t₄, t₅, or t₆ can be too short to induce a temperature variation, a heating or cooling step, or a heating or cooling session.

According to the invention, t₁, t₂, or t₃ can be shorter than t₄, t₅, or t₆ to enable the medium frequency to modulate the high frequency.

According to the invention, a sequence of duration t₇, t₈, t₉, t₁₀, t₁₁, or t₁₂ can be long enough to induce a temperature variation, a heating or cooling step, or a heating or cooling session.

According to the invention, a sequence of duration t₇, t₈, t₉, or t₁₀ can be shorter than t₁₁, or t₁₂ to enable the low frequency of oscillation to produce more temperature gradients than the very low frequency, where the very low frequency preferentially corresponds to the frequency of repetition of sessions.

In one embodiment of the invention, magnetic hyperthermia designates a method, technique, or process, preferentially of treatment or diagnosis, in which magnetic nanoparticles are exposed to an oscillating, producing (or not) a temperature increase, or producing (or not) the release of a compound from magnetic nanoparticles.

In one embodiment of the invention, the temperature increase is smaller than 10⁵, 10³, 150, 100, 75, 50, 25, 20, 15, 5, 2, 1, 0.1, 10⁻², 10⁻³, or 10⁻⁵° C., preferentially above the physiological temperature or the temperature of the body part, individual, or organism, preferentially measured before or without the application of the oscillating magnetic field or radiation.

In still another embodiment of the invention, the temperature increase is larger than 10⁵, 10³, 150, 100, 75, 50, 25, 20, 15, 5, 2, 1, 0.1, 10⁻², 10⁻³, or 10⁻⁵° C., preferentially above the physiological temperature or the temperature of the body part, individual, or organism, preferentially measured before or without the application of the oscillating magnetic field or radiation.

In an embodiment of the invention, the percentage of released compound is smaller than 10⁻¹⁵, 10⁻⁸, 10⁻⁴, 10⁻², 1, 5, 10, 25, 50, 75, 10², 10⁴, 10⁸, or 10¹⁵%, where this percentage can correspond to the quantity of compounds released after or during application of the oscillating magnetic field or radiation divided by the quantity of compounds bound or linked to the magnetic nanoparticles before or without the application of the oscillating magnetic field or radiation.

In still another embodiment of the invention, the percentage of released compound is larger than 10⁻¹⁵, 10⁻⁸, 10⁻⁴, 10⁻², 1, 5, 10, 25, 50, 75, 10², 10⁴, 10⁸, or 10¹⁵%. The situation where the percentage of released compound is larger than 100% is unlikely, but may for example happen if the released compound transforms itself in several compounds, hence increasing the number of released compounds.

In one embodiment of the invention, the oscillation of the magnetic field or radiation designates the oscillation or variation of the magnetic flux density, energy or power, with time, preferentially measured with a magnetic field or radiation probe in one or several directions, such as the axial and radial directions, most preferentially the axial and radial directions of a cylindrical magnetic field or radiation probe. In some cases, the magnetic flux density can be deduced from quantities such as the voltage measured by the probe, preferentially the voltage in the radial, U_(r), and axial, U_(a), directions, coefficients associated with the probe such as the radial and axial coefficients of the probe, α_(r) and α_(a), and one or several oscillation frequencies, preferentially the high frequency of oscillation f_(h), most preferentially using the formula H_(r)=U_(r)/α_(r)f_(h) and/or H_(a)=U_(a)/α_(a)f_(h), where H_(r) and H_(a) designate the magnetic flux density in the radial and axial directions, respectively.

In another embodiment of the invention, the magnetic flux density designates the strength of the magnetic field or radiation or another parameter such as the energy or power of the magnetic field or radiation.

In another embodiment of the invention, the frequency of oscillation can be estimated from the values of two times, t_(max1) and t_(max2), corresponding to two successive values of maximum flux density, as f=[1/(t_(max2)−t_(max1))] or f=[2π/(t_(max2)−t_(max1))]. In some other cases, the frequency of oscillation can be estimated from the values of two times, t_(min1) and t_(min2), corresponding to two successive values of minimum flux density, as f=[1/(t_(min2)−t_(min1))] or f=[2π/(t_(min2)−t_(min1))]. These formulas may preferentially be used to measure the high and/or medium frequency of oscillation, f_(h) and/or f_(m).

In another embodiment of the invention, the oscillation of the magnetic field or radiation designates the variation or oscillation of the magnitude of the magnetic flux density with time, H, where H can be deduced from the magnetic flux density, preferentially measured in the axial and radial directions, most preferentially using the relation: H=[H_(r) ^(2+H) _(a) ²]^(1/2). The magnitude of magnetic flux density can also designate the amplitude of the magnetic field or radiation.

In still another embodiment of the invention, the maximum magnetic field or radiation, H_(max), is defined as the maximum value of the magnitude of magnetic flux density oscillating with time. It preferentially corresponds to the maximum magnetic field or radiation amplitude estimated among the different values of local maximum magnetic field or radiation amplitude of each high frequency oscillation, designated as H_(max,i).

In another embodiment of the invention, H_(max,i) is a local maximum of magnetic field or radiation amplitude, estimated for each high frequency oscillation.

In still another embodiment of the invention, the average magnetic field or radiation, H_(av), is defined as the average value of the different values of H_(max,i), estimated for each high frequency oscillation.

In still another embodiment, H_(max,i), the average or maximum magnetic field or radiation, the strength or amplitude of the magnetic field or radiation, the high, low, or medium oscillation frequency can depend on a parameter of the device generating the oscillating magnetic field or radiation, such as the intensity, power, frequency of the alternating current, and can then be estimated for the various values of such parameter. H_(max,i), the average or maximum magnetic field or radiation, the strength or amplitude of the magnetic field or radiation, the high, low, or medium oscillation frequency, can also depend on the distance between the device and the magnetic nanoparticle, or on the distance between the device and the body part of the individual, or on the distance between the device and the region where one desires to apply the oscillating magnetic field or radiation, preferentially for heating magnetic nanoparticles. H_(max,i,) the average or maximum magnetic field or radiation, the strength or amplitude of the magnetic field or radiation, the high, low, or medium oscillation frequency can then be estimated as a function of such distance.

The description of the device generating the oscillating magnetic field or radiation is provided later in the description of the invention.

In one embodiment of the invention, the oscillating magnetic field or radiation is not generated by a medical device used for diagnosis, an MRI, a scanner, an equipment that does not generate a magnetic field or radiation oscillating at several different frequencies, or a permanent magnet.

In another embodiment of the invention, the oscillating magnetic field or radiation does not vary in space, or varies by less than 10⁹, 10⁷, 10⁵, 10³, 10, 1, 10⁻³, 10⁻⁵, 10⁻⁷, or 10⁻⁹ mT/m or 10⁻⁹ mT/cm or 10⁻⁹ mT/nm.

In one embodiment of the invention, for the magnetic field or radiation oscillating only at the high frequency, the relation between the average and maximum magnetic field or radiation can be H_(av)=H_(max), or the average magnetic field or radiation can be close, preferentially slightly lower, than the maximum magnetic field or radiation. The average magnetic field or radiation can preferentially be deduced from the relation: H_(av)=(Σ_(i=1) ^(i=n)H_(max,i)))/n, where H_(max,i) is the maximum magnitude of magnetic flux density estimated for each high frequency oscillation and n is the total number of high frequency oscillations.

In one embodiment of the invention, we consider that the magnetic field or radiation oscillates only at high frequency when the maximum magnetic field or radiation amplitude estimated for each high frequency oscillation does not vary, increase and/or decrease, or preferentially varies, increases and/or decreases, by less than 80, 60, 50, 40, 20, 10, 5, 2, or 1%. This percentage of variation is measured over a period of time that is preferentially lower than the heating and cooling times associated with the low frequency of oscillation, most preferentially lower than 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10⁻⁹, 1⁻¹⁰, 10⁻¹¹, or 10⁻¹² seconds.

In another embodiment of the invention, we consider that the magnetic field or radiation oscillates at high and medium frequency when the maximum magnetic field or radiation amplitude estimated for each high frequency oscillation, H_(max,i), varies, increases and/or decreases, preferentially by more than 80, 60, 50, 40, 20, 10, 5, 2, or 1%. This percentage of variation is measured over a period of time that is preferentially lower than the heating and cooling times associated with the low frequency of oscillation, most preferentially lower than 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10⁻⁹, 10⁻¹⁰, 10⁻¹¹, or 10⁻¹² seconds.

In another embodiment of the invention, for the magnetic field or radiation oscillating at the high and medium frequency, the maximum magnetic field or radiation, H_(max), is the maximum amplitude of the magnetic field or radiation, estimated among n high oscillation frequencies, and/or estimated among n values of H_(max,i).

In another embodiment of the invention, for the magnetic field or radiation oscillating at the high and medium frequency, the average magnetic field or radiation, H_(av), can be deduced from the relation: H_(av)=(Σ_(i=1) ^(i=n)H_(max,i))/n, where H_(max,i) is the maximum amplitude of the magnetic field or radiation estimated for each high frequency oscillation and n is the total number of high frequency oscillations, which are measured.

In one embodiment of the invention, for the magnetic field or radiation oscillating at the high and medium frequency, there is a relation between the maximum and average magnetic field or radiation and the average magnetic field or radiation can hence be deduced from the maximum magnetic field or radiation.

In one embodiment of the invention, for the magnetic field or radiation oscillating at the high, medium, and low frequency, the average magnetic field or radiation, estimated during the two sequences of times t₇ and t₈ (FIG. 2(b)) is defined as the average value between the average magnetic field or radiation estimated during the A₇ low frequency sequence, H_(A7), and the average magnetic field or radiation estimated during the A₈ low frequency sequence, H_(A8), as H_(av)=[(t₇.H_(A7)+t₈H_(A8))/(t₇+t₈)].

In some cases, a sequence can correspond to one or several session(s) or a session can correspond to one or several sequence(s).

In one embodiment of the invention, for the magnetic field or radiation oscillating at the high, and low frequency, the average magnetic field or radiation, estimated during the times t₉ and t₁₀ (FIG. 2(c)), is defined as the average value between the average magnetic field or radiation estimated during the A₉ low frequency sequence, H_(A9), and the average magnetic field or radiation estimated during the A₁₀ low frequency sequence, H_(A10), as H_(av)=[(t₉.H_(A9)+t₁₀.H_(A10))/(t₉+t₁₀)].

In one embodiment of the invention, t₇, H_(A7), t₈, H_(A8), t₉, H_(A9), t₁₀, or H_(A10), is/are average value(s) estimated from several A₇, A₈, A₉, or A₁₀ low frequency sequences.

In another embodiment of the invention, A₇, A₈, A₉, or A₁₀, correspond to the magnetic field or radiation amplitude, estimated during the A₇, A₈, A₉, or A₁₀ low frequency sequence.

In one embodiment of the invention, for the magnetic field or radiation oscillating at the high, medium, and low frequency, the maximum magnetic field or radiation is defined as the maximum magnetic field or radiation estimated during the A₇ low frequency sequence.

In one embodiment of the invention, for the magnetic field or radiation oscillating at the high and low frequency, the maximum magnetic field or radiation is defined as the maximum magnetic field or radiation estimated during the A₉ low frequency sequence.

The definitions of the sequences and times associated with them are provided later in the description.

In one embodiment of the invention, there is a stabilization time after the device generating the oscillating magnetic field or radiation has been switched on during which the magnetic field or radiation strength or amplitude preferentially increases until it reaches a plateau corresponding to magnetic field or radiation stabilization. In some cases, this stabilization time is longer than 1, 10, 50, 100, 200, 500, or 1000 seconds. In some cases, this stabilization time is shorter than 1, 10, 50, 100, 200, 500, or 1000 seconds.

In another embodiment of the invention, a stable magnetic field or radiation has not been reached before the stabilization time and the magnetic field or radiation is then designated as an unstable magnetic field or radiation. Such unstable magnetic field or radiation can be characterized by a maximum or average magnetic field or radiation that varies by more than 80, 50, 20, 10, 5, 2, or 1% with time, where this percentage is preferentially measured during a period of time of less than 60, 30, 15, 5, 1, or 0.1 minute.

In another embodiment of the invention, the average and maximum magnetic field or radiation, or the magnetic field or radiation strength or amplitude, of an unstable magnetic field or radiation can be estimated by multiplying the value of the average or maximum magnetic field or radiation, or of the magnetic field or radiation strength or amplitude, obtained for the same magnetic field or radiation, estimated after stabilization, by a factor, preferentially comprised between 0 and 1. The relation between stable and unstable magnetic field or radiation can preferentially be estimated using a pre-calibration curve that estimates the variation of the amplitude or strength of the magnetic field or radiation, or maximum or average magnetic field or radiation, as a function of time, preferentially within the stabilization time period, preferentially estimated with the magnetic field or radiation probe, most preferentially estimated for the device that generates the oscillating magnetic field or radiation. This relation can depend on a parameter of the device generating the oscillating magnetic field or radiation, such as the intensity, power, frequency of the alternating current, and can hence be estimated for the various values of such parameter. This relation can also depend on the distance between the device and the magnetic nanoparticle or on the distance between the device and the body part of the individual, or on the distance between the device and the region where one desires to apply the oscillating magnetic field or radiation, preferentially for heating magnetic nanoparticles. This relation can hence be estimated as a function of such distance.

In one embodiment of the invention, the oscillating magnetic field or radiation designates a magnetic field or radiation whose strength varies as a function of time between positive and negative values. The absolute value of the magnetic field or radiation strength corresponds to the amplitude of the oscillating magnetic field or radiation. The maximum and minimum strengths, of opposite signs, are usually of equal amplitude, but it can happen that maximum and minimum strengths differ by more than 1, 5, 10, 50, 75, or 80%.

In still another embodiment of the invention, the frequency of oscillation of the magnetic field or radiation, f, and associated period, T, where T and f are preferentially related to each other by the formula T=1/f, vary with parameters such as time of application of the oscillating magnetic field or radiation, current intensity, distance between the device generating the magnetic field or radiation and the magnetic nanoparticle, distance between the device generating the magnetic field or radiation and the body part of the individual, or the parameter of the device. It is then preferentially possible to define a frequency of oscillation or associated period for each value of such parameter i as f_(i) and T_(i)=1/f_(i). In this case, it may also be possible to define an average frequency of oscillation and associated period over n different values of such parameter as: f_(av)=(Σ_(i=l) ^(i=n)f_(i))/n and T_(av)=(Σ_(i=l) ^(i=n)T_(i))/n. It may also be possible to define the maximum frequency of oscillation and associated period, f_(max) and T_(max), as the maximum values of f_(i) and T_(i) over n different values of such parameter. It may also be possible to define the average frequency of oscillation and associated period as: H_(av)=(Σ_(i=l) ^(i=n)T_(i)H_(max,i))/(Σ_(i=l) ^(i=n)T_(i)).

In still another embodiment of the invention, the frequency of oscillation, f, and associated period, T, where T=1/f, vary with parameters such as time, current intensity, distance between the device generating the magnetic field or radiation and the magnetic nanoparticle, the distance between the device generating the oscillating magnetic field or radiation and the body part of the individual, or the parameter of the device, it is possible to determine a relation between the variation of the oscillation frequency, Δf, or of the variation of its associated period, ΔT, and the variation of parameters, such as variations of the time of application of the oscillating magnetic field or radiation, of current intensity, of distance between the device generating the magnetic field or radiation and the magnetic nanoparticle, of distance between the device generating the magnetic field or radiation and the body part of the individual, or of the parameter of the device.

In still another embodiment of the invention, the frequency of oscillation f_(i), or associated period, T_(i), is different from another frequency of oscillation or from another associated period, T_(j), when [(f_(i)−f_(j))/f_(i)] or [(T_(i)−T_(j))/T_(i)] is larger than 1, 5, 10, 25, 50, 70, 80, or 90%.

In still another embodiment of the invention, the frequency of oscillation f_(i), or associated period, T_(i), is the same as the frequency of oscillation f_(j), or associated period, T_(j), when [(f_(i)−f_(j))/f_(i)] or [(T_(i)−T_(j))/T_(i)] is lower than 1, 5, 10, 25, 50, 70, 80, or 90%.

In still another embodiment of the invention, the high, the medium, and/or the low frequency of oscillation of the magnetic field or radiation, comprises more or less than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 50, or 100 different frequencies of oscillation.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the average or maximum magnetic field or radiation, can be varied or adjusted by varying the intensity of the alternating current that generates the oscillating magnetic field or radiation, preferentially from 10⁻²⁰ to 10²⁰ A, from 10⁻¹⁵ to 10¹⁵ A, from 10⁻¹⁰ to 10¹⁰ A, from 10⁻⁵ to 10⁵ A, from 10⁻⁴ to 10⁴ A, from 10⁻³ to 10³ A, or from 0 to 500 A (Ampere).

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the average or maximum magnetic field or radiation, can be varied or adjusted by increasing the intensity of the alternating current that generates the oscillating magnetic field or radiation above 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10², 500, 10³, or 10⁵ A.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the average or maximum magnetic field or radiation, can be varied or adjusted by varying the power of the equipment generating the alternating current, preferentially from 10⁻²⁰ to 10²⁰ W, from 10⁻¹⁵ to 10¹⁵ W, from 10⁻¹⁰ to 10¹⁰ W, from 10⁻⁵ to 10⁵ W, from 10⁻⁴ to 10⁴ W, from 10⁻³ to 10³ W, or from 0 to 500 W (Watt).

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the average or maximum magnetic field or radiation, can be varied or adjusted by setting the power of the equipment generating the alternating current to a value, which is larger than 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10², 10³, or 10⁵ W or W per cm³ of exposed body part.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the average or maximum magnetic field or radiation, can be varied or adjusted by varying the distance separating the device generating the alternating currents from the magnetic nanoparticles or from the body part of the individual, preferentially by or to a distance comprised between 10⁻²⁰ to 10²⁰ cm, from 10⁻¹⁵ to 10¹⁵ cm, from 10⁻¹⁰ to 10¹⁰ cm, from 10⁻⁵ to 10⁵ cm, from 10⁻⁴ to 10⁴ cm, from 10⁻³ to 10³ cm, or from 0 to 500 cm. In some cases, the distance separating the device generating the alternating currents from the magnetic nanoparticles or from the body part of the individual is larger than 10⁻²⁰, 10⁻¹⁵, 10⁻¹⁰, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻¹, 1, 5, 10, or 20 cm.

In one embodiment of the invention, the amplitude of the oscillating magnetic field or radiation varies by more than 10⁻⁹, 10⁻⁶, 10⁻⁴, 10⁻², 1, 10, 10³, 10⁴, or 10⁶ mT per μm, per cm, or per m. In this case, it may be possible that the oscillating magnetic field or radiation induces a movement of the magnetic nanoparticles, of more than 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10², 10³, 10⁵, 10⁸, or 10¹¹ μm.

In another embodiment of the invention, the amplitude of the oscillating magnetic field or radiation varies by less than 10⁻⁹, 10⁻⁶, 10⁻⁴, 10⁻², 1, 10, 10³, 10⁴, or 10⁶ mT per μm, per cm, or per m. In this case, it may be possible that the oscillating magnetic field or radiation does not induce any movement of the magnetic nanoparticles, or a movement of less than 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10², 10³, 10⁵, 10⁸, or 10¹¹ μm.

In one embodiment of the invention, the nanoparticle, also designated as (the) nanoparticle(s) or as (the) magnetic nanoparticle(s), designates an assembly of more than 1, 2, 5, 10, 10², 10³, 10⁵, 10⁷, 10¹⁰, 10²⁰, or 10⁵⁰ magnetic nanoparticle(s).

In one embodiment of the invention, an oscillating magnetic field or radiation, preferentially oscillating at high frequency, or at high and medium frequency, is a magnetic field or radiation whose strength or amplitude oscillates with time, where one oscillation corresponds to the repetition of the same sequence more than once or to two or three different sequences, where sequences are defined as: i), a sequence of magnetic field or radiation amplitude or strength increase during a time t₁ associated to the high frequency, or a sequence of magnetic field or radiation amplitude or strength increase during a time t₄ associated to the medium frequency, ii), a sequence of magnetic field or radiation amplitude or strength decrease during a time t₂ associated to the high frequency, or a sequence of magnetic field or radiation amplitude or strength decrease during a time is associated to the medium frequency, iii), a sequence of constant magnetic field or radiation amplitude or strength during a time t₃ associated to the high frequency, or a sequence of constant magnetic field or radiation amplitude or strength during a time t₆ associated to the medium frequency. During t₃ or t₆, the magnetic field or radiation is preferentially of zero strength or amplitude. FIGS. 1(a) and 1(b) represent schematic pictures of the variation of magnetic field or radiation amplitude with time with indications of the different sequences for the magnetic field or radiation oscillating only at high frequency (FIG. 1(a)) or at high and medium frequency (FIG. 1(b)). Preferentially, sequences in FIG. 1(a) are designated as high frequency sequences while those in FIG. 1(b) correspond to medium frequency sequences.

In one embodiment of the invention, a sequence of magnetic field or radiation increase, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, corresponds to the time period t₁ or t₄ during which the amplitude of the magnetic field or radiation increases, preferentially continuously, by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, or 20 mT, or from less than 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 500, or 1000 mT, to more than 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 500, or 1000 mT, or by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, 50, 75, 90, 90, or 100%. This percentage can correspond to [2(A_(max)−A_(min))/(A_(max)+A_(min))], where A_(max) and A_(min) are the maximum and minimum amplitudes of the oscillating magnetic field or radiation during the time t₁ or t₄, respectively.

In one embodiment of the invention, a sequence of magnetic field or radiation increase, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, corresponds to the time period t₁ or t₄ during which the strength of the magnetic field or radiation increases, preferentially continuously, increases by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, or 20 mT, or from less than −1000, −500, −100, −95, −85, −80, −75, −70, −65, −60, −55, −50, −45, −40, −35, −30, −25, −20, −15, −14, −13, −12, −11, −10, −9, −8, −7, −6, −5, −4, −3, −2, or −1 mT to more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 500, or 1000 mT, or increases by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, 50, 75, 90, 90, or 100%. This percentage can correspond to [2(S_(max)−S_(min))/(S_(max)+S_(min))], where S_(max) and S_(min) are the maximum and minimum strengths of the oscillating magnetic field or radiation during the time t₁ or t₄, respectively.

In one embodiment of the invention, a sequence of magnetic field or radiation decrease, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, corresponds to the time period t₂ or t₅ during which the amplitude of the magnetic field or radiation decreases, preferentially continuously, by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, or 20 mT, from more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 500, or 1000 mT, to less than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 500, or 1000 mT, or by more than 0.1, 1, 2, 5, 10, 50, 75, 90, 90, or 100%. This percentage can correspond to [2(A_(max)−A_(min))/(A_(max)+A_(min))], where A_(max) and A_(min) are the maximum and minimum amplitudes of the oscillating magnetic field or radiation during the time t₂ or t₅, respectively.

In one embodiment of the invention, a sequence of magnetic field or radiation decrease, for the magnetic field or radiation, preferentially oscillating at the high or medium and high frequency, corresponds to the time period t₂ or t₅ during which the strength of the magnetic field or radiation decreases, preferentially continuously, decreases by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, or 20 mT, or decreases from less than 1000, 500, 100, 95, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 mT to more than −1, −2, −3, −4, −5, −6, −7, −8, −9, −10, −11, −12, −13, −14, −15, −20, −25, −30, −35, −40, −45, −50, −55, −60, −65, −70, −75, −80, −85, −90, −95, −100, −500, or −1000 mT, or decreases by more than 0.001, 0.01, 0.1, 1, 2, 5, 10, 50, 75, 80, 90, or 100%. This percentage can correspond to [2(S_(max)−S_(min))/(S_(max)+S_(min))], where S_(max) and S_(min) are the maximum and minimum strengths of the oscillating magnetic field or radiation during the time t₂ or t₅, respectively.

In one embodiment of the invention, a sequence of constant magnetic field or radiation, for the magnetic field or radiation, preferentially oscillating at the high or medium frequency, corresponds to the time period t₃ or t₆ during which the amplitude of the applied magnetic field or radiation is constant, i.e. does not vary by more than 0.01, 0.1, 1, 2, 5, 10, or 20 mT, or by more than 1, 5, 10, 25, or 50%. This percentage can correspond to [2(A_(max)−A_(min))/(A_(max)+A_(min))], where A_(max) and A_(min) are the maximum and minimum amplitudes of the oscillating magnetic field or radiation during the time t₃ or t₆, respectively.

In another embodiment of the invention, a sequence of constant magnetic field or radiation, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, corresponds to the time period t₃ or t₆ during which the strength of the applied magnetic field or radiation is constant, i.e. does not vary by more than 0.01, 0.1, 1, 2, 5, 10, or 20 mT, or by more than 1, 5, 10, 25, or 50%. This percentage can correspond to [2(S_(max)−S_(min))/(S_(max)+S_(min))], where S_(max) and S_(min) are the maximum and minimum amplitudes of the oscillating magnetic field or radiation during the time t₃ or t₆, respectively.

In one embodiment of the invention, a sequence of constant magnetic field or radiation, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, can be a sequence of zero magnetic field or radiation and correspond to the time period t₃ or t₆ during which the magnetic field or radiation is not applied or is applied but with a strength or amplitude close to 0, preferentially an amplitude, which is lower than or equal to 100, 50, 25, 10, 5, 2, 1, 10⁻, 10⁻², 10⁻³, 10⁻⁶, 10⁻⁹ mT, or 0 mT.

In one embodiment of the invention, sequences of increase, decrease, or constant magnetic field or radiation follow each other in any order.

In one embodiment of the invention, a cycle of the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, corresponds to a combination of at least two sequences.

In one embodiment of the invention, a sequence or a cycle, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, is repeated more than 2, 3, 4, 5, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, 10²⁵, 10⁵⁰, or 10¹⁰⁰ times.

In another embodiment of the invention, for the magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, high frequency sequences of increase, decrease, and constant magnetic field or radiation, taking place during a time t₁+t₂+t₃ are associated with a high frequency cycle of high frequency f_(h) equal or proportional to [2π/(t₁+t₂+t₃)], or [1/(t₁+t₂+t₃)], preferentially when the frequency is estimated from the variation of the strength of the magnetic field or radiation with time, or are associated with a high frequency cycle of high frequency f_(h) equal or proportional to [π/(t₁+t₂+t₃)], or [½.(t₁+t₂+t₃)], preferentially when the frequency is estimated from the variation of the amplitude of the magnetic field or radiation with time.

In another embodiment of the invention, for the magnetic field or radiation, preferentially oscillating at high and medium frequency, sequences of increase, decrease, and constant magnetic field or radiation, taking place during a time t₄+t₅+t₆ are associated with a medium frequency cycle of medium frequency f_(m) equal or proportional to [2π/(t₄+t₅+t₆)], or [1/(t₄+t₅+t₆)], preferentially when the frequency is estimated from the variation of the strength of the magnetic field or radiation with time, or of medium frequency f_(m) equal or proportional to [π/(t₄+t₅+t₆)], or [½.(t₄+t₅+t₆)], preferentially when the frequency is estimated from the variation of the amplitude of the magnetic field or radiation with time.

In one embodiment of the invention, the time t₁, t₂, t₃, t₄, t₅, or t₆, is lower than 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10⁻⁹, 10⁻¹⁰, 10⁻¹¹, 10⁻¹¹, 10⁻¹², 10⁻¹², 10⁻¹³, 10⁻¹⁴, or 10⁻¹⁵ seconds.

In another embodiment of the invention, the time t₁, t₂, t₃, t₄, t₅, or t₆, is larger than 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10−⁹, 10⁻¹⁰, 10⁻¹¹, 10⁻¹¹, 10⁻¹², 10⁻¹², 10⁻¹³, 10⁻¹⁴, or 10⁻¹⁵ seconds.

In another embodiment of the inventions, the time t₄, t₅, or t₆, is 1,001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10, 10³, or 10⁶ larger than t₁, t₂, or t₃.

In one embodiment of the invention, for the oscillating magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, the times t₁ and t₁′ t₄ and t₄′ measured between 2 sequences of magnetic field or radiation increase, the times t₂ and t₂′ or t₅ and t₅′ measured between 2 sequences of magnetic field or radiation decrease, and the times t₃ and t₃′ or t₆ and t₆′ measured between 2 sequences of constant magnetic field or radiation, vary by more than 100, 75, 50, 25, 10, 5, 2, 1 10⁻¹, 10⁻², 10⁻³, or 10⁻⁴%, where this percentage can correspond to [(t₁−t₁′)/t₁], [(t₂−t₂′)/t₂], [(t₃−t₃′)/t₃], [(t₄−t₄′)/t₄], [(t₅- t₅′)/t₅], or [(t₆−t₆′)/t₆], or by more than a factor of 1.5, 2, 5, 10, 10², or 10⁵. In this case, the high or medium frequency is preferentially unstable.

In one embodiment of the invention, for the oscillating magnetic field or radiation, preferentially oscillating at the high or high and medium frequency, the times t₁ and t₁′ or t₄ and t₄′ measured between 2 sequences of magnetic field or radiation increase, the times t₂ and t₂′ or t₅ and t₅′ measured between 2 sequences of magnetic field or radiation decrease, and the times t₃ and t₃′ or t₆ and t₆′ measured between 2 sequences of constant magnetic field or radiation, vary by less than 100, 75, 50, 25, 10, 5, 2, 1, 10⁻¹, 10⁻², 10⁻³, or 10⁻⁴%, where this percentage can correspond to [(t₁−t₁′)/t₁], [t(t₂−t₂′)/t₂], [(t₃−t₃′)/t₃], [(t₄−t₄′)/t₄], [(t₅−t₅′)/t₅], or [(t₆−t₆′)/t₆], or by less than a factor of 1.5, 2, 5, 10, 10², or 10⁵. In this case, the high or medium frequency is preferentially stable.

In one embodiment of the invention, the oscillating magnetic field or radiation, preferentially oscillating at a high frequency, corresponds to that oscillating at a frequency f_(h), which is preferentially larger than 10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, or 10⁸ kHz.

In another embodiment of the invention, the high frequency of oscillation is preferentially used to heat the magnetic nanoparticles, i.e. it is preferentially sufficiently high to heat nanoparticles. In some cases, the high frequency of oscillation is sufficiently high to induce a rapid movement of the magnetic nanoparticles and/or an inversion of the magnetic moment of the magnetic nanoparticles, i.e. a movement and/or magnetic moment inversion that preferentially takes place within less than 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, or 10⁻⁹ seconds.

In still another embodiment of the invention, the high frequency of oscillation is used to heat the magnetic nanoparticles when the amplitude or strength of the magnetic field or radiation, or the maximum or average magnetic field or radiation, is/are sufficiently high to heat the nanoparticles, i.e. preferentially larger than 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, or 10⁵ T. In some case, the amplitude or strength of the magnetic field or radiation, or the maximum or average magnetic field or radiation, is sufficiently high to induce a movement of the magnetic nanoparticles and/or an inversion of the magnetic moment of the nanoparticle. In some case, the amplitude or strength of the magnetic field or radiation, or the maximum or average magnetic field or radiation, is larger than the coercivity of the magnetic nanoparticles, preferentially enabling inversion of the magnetic moment of the nanoparticle or the movement of the magnetic nanoparticle.

In still another embodiment of the invention, the high frequency of oscillation is too high, and/or the time t₂ is too short, to enable a decrease in temperature of the magnetic nanoparticles or of their surroundings, preferentially to yield a temperature decrease of more than 1, 5, 10, 50, or 100° C., preferentially when a suspension of magnetic nanoparticles, preferentially at a concentration of more than 0.1, 1, or 10 mg/mL is exposed to this magnetic field or radiation, preferentially when temperature is measured between at least 1, 10, 100, or 1000 high frequency oscillations or high frequency sequences. The fact that the high frequency of oscillation can't result in temperature decrease can be problematic in a magnetic hyperthermia treatment, since it can possibly lead to Eddy or Foucault currents or to other side effects due to continuous heating, possibly leading to overheating. This is the reason why it may appear necessary to add a low frequency of oscillation that produces cooling steps.

In one embodiment of the invention, cooling and heating steps are designated as cooling and heating phases. They can correspond to cooling and heating low frequency sequences.

In another embodiment of the invention, the oscillating magnetic field or radiation, preferentially oscillating at a medium frequency, corresponds to that oscillating at a medium frequency, f_(m), which is preferentially 1.1, 1.5, 2, 5, 10, 20, 30, 50, 10², 10³, 10⁶, or 10⁹ times lower than the high frequency, f_(h). This medium frequency, f_(m), can be an envelope function of the magnetic field or radiation oscillating at f_(h) and can thus be used to yield a strength or amplitude of the magnetic field or radiation, a maximum or average magnetic field or radiation, which is larger than that reached without this medium frequency.

In one embodiment of the invention, the oscillating magnetic field or radiation, preferentially oscillating at a low, medium, and high frequency, corresponds to a magnetic field or radiation comprising at least one sequence, preferentially designated as a low frequency sequence, during which the magnetic field or radiation strength or amplitude, or the maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is first constant at a value A₇ during a time t₇, preferentially if the magnetic field or radiation is stable, or increases up to a value A₇ during a time t₇, preferentially if the magnetic field or radiation is unstable, and at least another sequence, preferentially designated as another low frequency sequence, during which the magnetic field or radiation strength or amplitude, or maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is constant at a value A₈ during a time t₈, preferentially if the magnetic field or radiation is stable, or decreases down to A₈ during a time t₈, preferentially if the magnetic field or radiation is unstable, where A₈ is lower than A₇. FIG. 2(b) represents a schematic diagram of the A₇ and A₈ low frequency sequences. These two sequences can preferentially be repeated more than 1, 2, 3, 4, 5, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, 10²⁵, 10⁵⁰, or 10¹⁰⁰ times.

In one embodiment of the invention, the oscillating magnetic field or radiation, preferentially oscillating at the low and high frequency, corresponds to a magnetic field or radiation comprising at least one sequence, preferentially designated as a low frequency sequence, during which the magnetic field or radiation strength or amplitude, or the maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is first constant at a value A₉ during a time t₉, preferentially if the magnetic field or radiation is stable, or increases to a value A₉ during a time t₉, preferentially if the magnetic field or radiation is unstable, and at least another sequence, preferentially designated as another low frequency sequence, during which the magnetic field or radiation strength or amplitude, or maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is constant at another value A₁₀ during a time t₁₀, preferentially if the magnetic field or radiation is stable, or decreases down to A₁₀ during t₁₀, preferentially if the magnetic field or radiation is unstable, where A₁₀ is lower than A₉. FIG. 2(c) represents a schematic diagram of the A₉ and A₁₀ low frequency sequences. These two sequences can preferentially be repeated more than 1, 2, 3, 4, 5, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, 10²⁵, 10⁵⁰, or 10¹⁰⁰ times.

In an embodiment of the invention, sequence during which the magnetic field or radiation strength or amplitude, or the maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is constant at a value A₇ or A₉ during a time t₇ or t₉, or increases to A₇ or A₉ during t₇ or t₉, is called a A₇ or A₉ low frequency sequence. It may correspond to a heating step.

In one embodiment of the invention, the time t₇ or t₉ is sufficiently long, preferentially longer than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², or 10³ seconds, to enable the production and/or dissipation of heat by the magnetic nanoparticle, and preferentially of its surrounding, under the application of an alternating field, hence leading to a heating step.

In another embodiment of the invention, the surrounding of the magnetic nanoparticles is defined as the region surrounding or comprising them, i.e. preferentially a region comprising more than 1, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, or 10²⁰ nanoparticles, or the volume of the region comprising them, where this volume is preferentially estimated from the center of 1, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, or 10²⁰ nanoparticles, as being preferentially smaller than 1 m³, 1 cm³, 1 mm³, or 1 μm³.

In still another embodiment of the invention, the time t₇ or t₉ is sufficiently short, preferentially shorter than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², or 10³ seconds, preferentially to prevent a situation of overheating.

In another embodiment of the invention, sequence during which the magnetic field or radiation strength or amplitude, or maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency, is constant at a value A₈ or A₁₀ during the time t₈ or t₁₀, or increases to A₈ or A₁₀ during t₈ or t₁₀, is called a A₈ or A₁₀ low frequency sequence. It may correspond to a cooling step.

In one embodiment of the invention, the time t₈ or t₁₀ is sufficiently long, preferentially longer than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁴, 1, 10, 10², or 10³ seconds, to cool down the magnetic nanoparticle, and preferentially also its surrounding.

In still another embodiment of the invention, the times t₈ or t₁₀ are sufficiently short, preferentially shorter than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², or 10³ seconds.

In one embodiment of the invention, the magnetic field or radiation strength or amplitude, or the maximum or average magnetic field or radiation can be considered constant during t₇, t₈, t₉, and/or t₁₀ when they do not vary by more than 1, 2, 5, 10, 15, 25, 50, 75, 80 or 100%, where this percentage of variation may correspond to [(ε_(max)ε_(min))/ε_(max)], where ε_(max) and ε_(min) can be the maximum and minimum values measured during t₇, t₈, t₉, and/or t₁₀ of the magnetic field or radiation strength or amplitude, or of maximum or average magnetic field or radiation, estimated for the magnetic field or radiation oscillating only at high frequency or at high and medium frequency.

In one embodiment of the invention, a A₈ or A₁₀ low frequency sequence preferentially follows a A₇ or A₉ low frequency sequence, or a A₇ or A₉ low frequency sequence follows a A₈ or A₁₀ low frequency sequence, but it can happen that several A₈ or A₁₀ low frequency sequences follow each other or that several A₇ or A₉ low frequency sequences follow each other.

In still another embodiment of the invention, A₇ or A₉ is non-zero or much larger than the amplitude of the earth's magnetic field or radiation. A₇ or A₉ is preferentially lower than the magnetic field or radiation amplitude enabling to generate Eddy or Foucault currents. A₇ or A₉ is also preferentially larger than the amplitude of the magnetic field or radiation, which is necessary to heat magnetic nanoparticles, preferentially by magnetic hyperthermia, or larger than 0.01 mT, or 0.1 mT, or 1 mT, or 2 mT, or 3 mT, or 5 mT, or 7 mT, or 10 mT, or 15 mT, or 20 mT, or 25 mT, or 50 mT, or 100 mT, or 500 mT, or 1 T, or 10 T, or 100 T, or 10³ T.

In an embodiment of the invention, A₇ or A₉ is larger than 10⁻⁶, 10⁻⁴, 10⁻², 1, 10, 10², or 10³ Watt per cm³ of the body part.

In an embodiment of the invention, A₇ or A₉ is at least 1.1, 1.5, 2.5, 10, 25, 50, 100, 250, 500, 10³, 10⁵, 10¹⁰, or 10⁵⁰ times larger than A₈ or A₁₀.

In another embodiment of the invention, A₈ or A₁₀ is zero, corresponding to a zero magnetic field or radiation, when the magnetic field or radiation strength or amplitude, or maximum and average magnetic field or radiations, preferentially estimated at high or at high and medium frequency, are close to the amplitude of the earth's magnetic field or radiation or lower than the amplitude of a magnetic field or radiation, which generates Eddy or Foucault currents or less than a value of magnetic field or radiation amplitude, which enables to heat magnetic nanoparticles, preferentially by magnetic hyperthermia, or lower than 10³ T, or 100 T, or 10 T, or 1 T, or 500 mT, or 100 mT, or 50 mT, or 25 mT, or 10 mT, or 5 mT, 1, 10⁻¹, 10⁻³, or 10⁻⁶ mT.

In another embodiment of the invention, A₈ or A₁₀ is lower than 10⁻⁶, 10⁻⁴, 10⁻², 1, 10, 10², or 10³ Watt per cm³ of the body part.

In one embodiment of the invention, the times t₇ and t₇′, t₈ and t₈′, t₉ and t₉′, t₁₀ and t₁₀′, measured between two A₇, A₈, A₉, or A₁₀ low frequency sequences, respectively, vary by more or less than 100, 75, 50, 25, 10, 5, 2, 1 10⁻¹, 10⁻², 10⁻³, or 10⁻⁴%, where this percentage can correspond to [(t₇−t₇′)/t₇], [(t₈−t₈′)/t₈], [(t₉−t₉′)/t₉], or [(t₁₀−t₁₀′)/t₁₀], or vary by a factor of more or less than 1.1, 2, 5, 10, 10², 10³, or 10⁵.

In one embodiment of the invention, a combination of a A₇ low frequency sequence with a A₈ low frequency sequence or of a A₉ low frequency sequence with a A₁₀ low frequency sequence corresponds to a low frequency cycle.

In another embodiment of the invention, a low frequency cycle, taking place during a time t₇+t₈ or t₉+t₁₀, is associated with a low frequency cycle of low frequency f_(l) equal or proportional to [2π/(t₇+t₈)], [1/(t₇+t₈)], [2π/(t₉+t₁₀)], or [1/(t₉+t₁₀)].

In one embodiment of the invention, a low frequency sequence or a low frequency cycle is repeated more than 2, 3, 4, 5, 10, 10², 10³, 10⁴, 10⁵, 10¹⁰, 10²⁵, 10⁵⁰, or 10¹⁰⁰ times.

In another embodiment of the invention, a magnetic field or radiation oscillating at a low frequency corresponds to a magnetic field or radiation oscillating at a frequency f_(l), which is preferably between 10⁻⁶ Hz and 10⁶ Hz. This low oscillation frequency may produce multiple successive heating and cooling steps. This low frequency may be chosen to yield maximum treatment efficacy and minimum treatment toxicity, especially during a magnetic hyperthermia treatment.

In still another embodiment of the invention, f_(l) is smaller than 10⁶, 10⁵, 10⁴, 10³, 10², 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, or 10⁻⁶ Hz. In some cases, f_(l) can also be between 0.2 10⁻² Hz and 0.3 10⁻¹ Hz, or between 0.02 10⁻² Hz and 3 10⁻¹ Hz, or between 0.002 10⁻² Hz and 30 10⁻¹ Hz. In some cases, f_(l) can also be more than 1.01, 1.1, 1.5, 2, 5, 10, 10², 10³, 10⁵, 10⁸, 10″, or 10²⁰ times lower than f_(m) or f_(h). In some other cases, f_(l)can also be less than 1.01, 1.1, 1.5, 2, 5, 10, 10², 10³, 10⁵, 10⁸, 10¹¹, or 10²⁰ times lower than f_(m) or f_(h).

In still another embodiment of the invention, f₁ is larger than 10⁶, 10⁵, 10⁴, 10³, 10², 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, or 10⁻⁶ Hz.

In one embodiment of the invention, a heating step combined with a cooling step corresponds to a low frequency cycle.

In another embodiment of the invention, maximal temperatures, T_(max), and minimal temperatures, T_(min), are defined as the maximal temperatures reached during the heating steps or low frequency sequences A₇ or A₉, and minimal temperatures reached during the cooling steps or low frequency sequences A₈ or A₁₀.

In another embodiment of the invention, T_(max) and/or T_(min) varies or vary between two low frequency cycles by more or less than 1, 5, 10, 15, 20, 50, 75, 80, or 90%, where this percentage can correspond to [2(T_(max)−T_(min))/(T_(max)+T_(min))].

In another embodiment of the invention, the oscillating magnetic field or radiation is applied during a session, preferentially a heating session. The duration of a heating session is designated by t₁₁ while the time separating two different heating sessions is designated by t₁₂.

According to the invention, a session can be repeated more than 2, 5, or 10 times, preferentially with a very low frequency f_(v1), which can be measured using the formula: f_(v1)=1/[2π(t₁₁+t₁₂)] or f_(v1)=1/(t₁₁+t₁₂). f_(v1) is preferentially lower than 1, 10⁻³, 10⁻⁶, or 10⁻⁹ Hz, or 2, 5, 10, 10³, 10⁹, or 10²⁰ times lower than f_(l), f_(m), or f_(h).

In another embodiment of the invention, a session is associated with the time during which an alternating magnetic field or radiation is applied, most preferentially a time during which a typical magnetic hyperthermia treatment takes place, i.e. typically more or less than 10⁻⁹, 10⁻⁶, 10⁻³, 1, 10³, 10⁶, or 10⁹ minutes.

In one embodiment, a heating step or a heating session corresponds to a lapse of time during which a temperature increase occurs.

According to the invention, the temperature increase can in some cases either be measurable, preferentially using a standard thermometry method, or not be measurable in some other cases, preferentially using a standard thermometry method. It can have the same meaning as hyperthermia or magnetic hyperthermia.

The standard thermometry method, according to the invention, can be a method that enables temperature measurement at a larger scale than the cellular or nanometer scale. It may measure the temperature macroscopically within a tissue, an organ, or a tumor for example but may preferentially not measure the temperature around nanoparticles, or inside or just around cells.

In one embodiment of the invention, the temperatures reached during treatment, may include temperature gradients, a temperature that one wants to achieve, a given temperature, a temperature probe, a constant temperature, a temperature decrease, a temperature increase, a temperature variation, a temperature of the magnetic nanoparticles, a maximal or maximum temperature, a minimal or minimum temperature, a measure of temperature macroscopically, or a temperature around nanoparticles. These temperatures can indicate a physico-chemical disturbance reached during treatment, physico-chemical disturbance gradients, a physico-chemical disturbance that one wants to achieve, a given physico-chemical disturbance, a physico-chemical disturbance probe, a constant physico-chemical disturbance, a physico-chemical disturbance decrease, a physico-chemical disturbance increase, a physico-chemical disturbance variation, a physico-chemical disturbance of the magnetic nanoparticles, a maximal or maximum physico-chemical disturbance, a minimal or minimum physico-chemical disturbance, a measure of physico-chemical disturbance macroscopically, or a physico-chemical disturbance around nanoparticles, respectively.

In another embodiment of the invention, heating, continuous heating, overheating, heating steps, heating phases, heating low frequency sequences, heating session, heating the nanoparticles, heating times, or heating gradients, can indicate an increase in physico-chemical disturbance, a continuous increase in physico-chemical disturbance, too large of an increase in physico-chemical disturbance, steps of a physico-chemical disturbance increase, phases of a physico-chemical disturbance increase, low frequency sequences of a physico-chemical disturbance increase, a session of a physico-chemical disturbance increase, application of an increased physico-chemical disturbance to nanoparticles, times of a physico-chemical disturbance increase, or gradients of a physico-chemical disturbance increase, respectively.

In another embodiment of the invention, cooling, continuous cooling, cooling steps, cooling phases, cooling low frequency sequences, a cooling session, cooling the nanoparticles, cooling times, or cooling gradients, can indicate a decrease in physico-chemical disturbance, a continuous decrease in physico-chemical disturbance, too large of a decrease in physico-chemical disturbance, steps of a physico-chemical disturbance decrease, phases of a physico-chemical disturbance decrease, low frequency sequences of a physico-chemical disturbance decrease, a session of a physico-chemical disturbance decrease, application of a decreasing physico-chemical disturbance to nanoparticles, times of a physico-chemical disturbance decrease, or gradients of a physico-chemical disturbance decrease, respectively.

In another embodiment of this invention, the physico-chemical disturbance can be associated with more than one of the following physico-chemical disturbance parameters: (i), the application of the magnetic field or radiation oscillating at high frequency and, at medium and/or low frequency, (ii), the movement of the nanoparticles, by more or less than 1 nm, 10 nm, 100 nm, 1 μm, 10 μm, 100 μm, 1 mm, 10 mm, 1 cm, 10 cm or 1 m, (iii), the release or dissociation of a substance or compound from the nanoparticle, (iv), a change in the composition of the nanoparticle, (v), a variation in the pH of the nanoparticle by more or less than 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 pH unit(s), (vi), a variation in redox potential of the nanoparticle by more or less than 1 V, 100, 10, 1, or 0.1 mV, or (vii), a variation in the surrounding of the nanoparticle such as a variation in pH, temperature, redox potential, or chemical composition of this surrounding.

In another embodiment of the invention, the increase in physico-chemical disturbance is associated with the increase by more than 1, 5, 10, 25, 50, 75, or 90% or by a factor of more than 1.2, 2, 5, 10, or 10² of the physico-chemical disturbance parameter.

In another embodiment of the invention, the decrease in physico-chemical disturbance is associated with the decrease by more than 1, 5, 10, 25, 50, 75, or 90% or by a factor of more than 1.2, 2, 5, 10, or 10² of the physico-chemical disturbance parameter.

The invention also relates to magnetic nanoparticles for use, in which the low frequency of oscillation includes at least one cycle comprising a step with increasing physico-chemical disturbance and a step with decreasing physico-chemical disturbance.

In still another embodiment of the invention, t₁₁ is larger than 10⁻⁹, 10⁻⁶, 10⁻³, 1, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁹, or 10²⁰ seconds. It can be comprised between 1 and 30 minutes, 1 and 12 hours, or 1 and 15 days. The value of t₁₁ can correspond to the time during which the individual can be treated, preferentially without any side effects. It is preferentially lower than the time of anesthesia of the individual. It preferentially corresponds to the time during which the medical team in charge of the treatment of the individual is available or to the time during which the alternating magnetic field or radiation or radiation can be applied.

In still another embodiment of the invention, t₁₁ smaller than 10⁻⁹, 10⁻⁶, 10⁻³, 1, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁹, or 10²⁰ seconds.

In still another embodiment of the invention, t₁₁ is 1, 1.0001, 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10², 10³, or 10⁵ larger than t₇, t₈, t₉, t₁₀, t₇+t₈, or t₉+t₁₀.

In still another embodiment of the invention, the time separating two sessions corresponds to the time necessary for the individual or patient or medical team to rest between two treatments, or the time necessary to switch off the device generating the magnetic field or radiation.

In still another embodiment of the invention, t₁₂ is larger than 10⁻⁹, 10⁻⁶, 10⁻³, 1, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁹, or 10²⁰ seconds.

In still another embodiment of the invention, t₁₂ is lower than 10⁻⁹, 10⁻⁶, 10⁻³, 1, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁹, or 10²⁰ seconds.

In still another embodiment of the invention, t₁₂ is 1, 1.0001, 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10², 10³, or 10⁵ larger than t₇, t₈, t₉, t₁₀, t₇+t₈, t₉+t₁₀, or t₁₁.

In another embodiment of the invention, the application of the magnetic field or radiation, preferentially oscillating at the high and, medium and/or low frequency, corresponds to the production of a magnetic field or radiation applied by a source of energy, most preferentially a source of energy manufactured or controlled by the individual. It can correspond to the application of a magnetic field or radiation that can heat magnetic nanoparticles, where heat can preferentially be measured with a thermometry method, preferentially a standard thermometry method, using for example an infrared camera or a thermocouple.

In another embodiment of the invention, the non-application of the magnetic field or radiation, preferentially oscillating at the high, medium and/or low frequency, also designated as zero magnetic field or radiation, corresponds to the application of a magnetic field or radiation whose strength or amplitude is very weak, such as the application of the earth magnetic field or radiation or of the magnetic field or radiation generated by instruments working with currents or magnets, whose purpose is not to heat nanoparticles but that create a non-negligible magnetic field or radiation. In some cases, the non-application of the oscillating magnetic field or radiation can also take place during the application of a magnetic field or radiation whose amplitude can be less than the amplitude necessary to heat magnetic nanoparticles. In some cases, the non-application of the oscillating magnetic can correspond to the application of a magnetic field or radiation outside of the region where magnetic nanoparticles are located, or outside of the body part of the individual.

In another embodiment of the invention, the magnetic field or radiation, preferentially oscillating at the high and, medium and/or low frequency, is applied in the region comprising magnetic nanoparticles. This region may preferentially comprise more than 1, 10, 10², 10³, 10⁶, 10¹², 10²⁰, 10⁵⁰, or 10¹⁰⁰ magnetic nanoparticles, or more than 1, 5, 10, 25, 50, 75, 90, or 95% of the administered nanoparticles, where this percentage can correspond to the number of nanoparticles in the region where magnetic nanoparticles are administered divided by the total number of administered nanoparticles. This region may also preferentially comprise more than 1, 5, 10, 25, 50, 75, 90, or 95% of the nanoparticles exposed to the oscillating magnetic field or radiation, where this percentage can correspond to the number of nanoparticles exposed to the oscillating magnetic field or radiation divided by the total number of nanoparticles, preferentially comprised in the body part of the individual.

In another embodiment of the invention, the oscillation of the magnetic field or radiation, preferentially at the high and, medium and/or low frequency, comprises the variation, decrease, or increase with time of the magnetic field or radiation strength or amplitude, or of the maximum or average magnetic field or radiation, or comprises a constant magnetic field or radiation strength or amplitude, maximum or average magnetic field or radiation with time, or comprises a combination of varied, decreasing, increasing, or constant magnetic field or radiation with time.

In still another embodiment of the invention, the oscillation of the magnetic field or radiation comprises the variation, decrease, or increase with time of the energy or power of the oscillating magnetic field or radiation, or comprises a constant energy or power of the oscillating magnetic field or radiation with time, or comprises a combination of varied, decreasing, increasing, or constant energy or power of the oscillating magnetic field or radiation with time.

In another embodiment of the invention, the oscillation of the magnetic field or radiation with time is represented, or modeled, by a function such as a numerical function, a zero, identity, square, cube, inverse, constant, linear, second degree, power, holographic, laurentian, cubic root, affine, polynomial, rational, absolute value, sign Heaviside, count of prime numbers, integer part, fractional part, sinus, cosine, tangent, cotangent, arc sinus, arc cosine, tangent arc, Dirichlet, exponential, logarithmic, hyperbolic, sigmoid, Brillouin, Langevin, gamma, beta, integral, logarithm, integral, Bessel, harmonic and associated, or arithmetic function, or a derivative, or a combination of one or several of these functions.

In another embodiment of the invention, such function is determined by first measuring the oscillation of the magnetic field or radiation with time, by using a probe, and then by adjusting this measurement with this function, preferably using suitable computer software, such as “origin”.

In still another embodiment of the invention, the frequency of oscillation, f, and associated period, T, where T=1/f, vary with parameters such as time, current intensity, distance between the device generating the magnetic field or radiation and the magnetic nanoparticle, distance between the device generating the magnetic field or radiation and the body part of the individual, or the parameter of the device, it is possible to determine a relation between the variation of the oscillation frequency, Δf, or between the variation of its associated period, ΔT, and the variation of parameters, such as variations of the time of application of the oscillating magnetic field or radiation, of current intensity, of power, of distance between the device generating the magnetic field or radiation and the magnetic nanoparticle, or of the parameter of the device. In some cases, such relation can be represented or modeled by one or several of these functions.

In another embodiment of the invention, the oscillation of the magnetic field or radiation with time, produces a symmetrical oscillation of the magnetic field or radiation, i.e. the function describing such oscillation is a symmetric function, in which the symmetry can preferentially be observed from at least one time point of the variation.

In another embodiment of the invention, the oscillation of the magnetic field or radiation with time is symmetrical, preferentially when the ratio [t_(i)/t_(j)], is lower than 10⁻⁶, 10⁻³, 10⁻¹, 1, 10, 10³, or 10⁶, where t, t_(i)≠t_(j) and i and j are preferentially numbers between 1 and 10 and t₁ to t₁₀ have previously been defined.

In another embodiment of the invention, the oscillation of the magnetic field or radiation with time is asymmetric, i.e. the function describing such oscillation is an asymmetric function, where the asymmetry can be observed from at least one time point of the oscillation. In another embodiment of the invention, the oscillation of the magnetic field or radiation with time is asymmetric when the ratio [t_(i)/t_(j)] is larger than 10⁻⁶, 10⁻³, 10⁻¹, 1, 10, 10³, or 10⁶, or [t_(i)/t_(j)] is lower than 10⁻⁶, 10⁻³, 10⁻¹, 1, 10, 10³, or 10⁶, where t_(i)≠t_(j) and i and j are numbers, preferentially between 1 and 10.

In one embodiment of the invention, magnetic hyperthermia is a method or a method of treatment, preferably used to treat the body part of the individual, or pathological cells, such as prokaryotic or eukaryotic cells, most preferentially tumors. In this method, magnetic materials, such as magnetic nanoparticles, are preferentially introduced in the body part of the individual or sent to body part of the individual and exposed to an oscillating magnetic field or radiation, preferentially producing a temperature increase of the nanoparticles and preferentially also of the nanoparticle surrounding. The treatment can result from the change of any parameter that results from the application of the oscillating magnetic field or radiation on the magnetic nanoparticles brought into contact, mixed, or assembled with the cells, entity, or body part of the individual.

In one embodiment of the invention, magnetic hyperthermia is a diagnosis method, preferably used to detect a specific condition, such as an illness, of the individual, or specific cells, such as prokaryotic or eukaryotic cells, pathological cells, such as tumor cells, or an entity or materials that originate from such cells or individual. In this method, magnetic materials, such as magnetic nanoparticles, are preferentially brought into contact or mixed or assembled with cells, the entity, body part of the individual and exposed to the oscillating magnetic field or radiation, preferentially producing a temperature increase of the nanoparticles and preferentially also of the nanoparticle surrounding. The diagnosis can be based on the detection of temperature or on the change of any parameter that results from the application of the oscillating magnetic field or radiation on the magnetic nanoparticles brought into contact, mixed, or assembled with the cells, entity, or body part of the individual.

In one embodiment of the invention, the body part of the individual designates any part of a living or dead individual or organism, where such individual or organism preferentially contains more than one prokaryotic or eukaryotic cell. Such individual or organism can be a unicellular or multicellular organism, a plant, a human, an animal, a bacterium, an archaea, or a fungus. It can be a tissue, an organ, blood, skin, an arterial, bone, DNA, RNA, a protein, a lipid, an enzyme, one or an assembly of amino acids or nucleic acids, or biological material. It can represent one or several part(s) of the individual or organism or a whole individual or organism. The body part of the individual preferentially represents the part, which is treated. It can also designate the whole individual or any biological material, preferentially originating or extracted from a living organism or from the individual.

In one embodiment of the invention, body part of the individual belongs to the respiratory system, the digestive, respiratory, nervous, muscular, or skeletal system. They may also belong to a tumor, infected tissue or infected assembly of cells, possibly containing bacteria or viruses, which may belong to at least one of these systems.

In one embodiment, body part of the individual contains more than 1, 10, 10³, 10⁶, 10⁹, or 10¹³ magnetic nanoparticles. In some cases, body part of the individual can be associated with the magnetic nanoparticles, for example when the nanoparticles are opsonized.

In another embodiment of the invention, a magnetic hyperthermia therapeutic treatment method is a method in which magnetic nanoparticles are exposed to a magnetic field or radiation, preferentially oscillating at the high and, medium and/or low frequency. In this method, the exposure of magnetic nanoparticles to the oscillating magnetic field or radiation preferentially induces a temperature increase and/or a movement of the nanoparticles, which preferentially lead(s) to a specific interaction and/or transformation of body part of the individual. Such specific interaction and/or transformation can be the internalization or externalization of nanoparticles in/from cells, the death of cells, preferentially by apoptosis or necrosis, where these cells preferentially belong to body part of the individual.

The present invention concerns magnetic nanoparticles for use in a magnetic hyperthermia diagnosis method, wherein the magnetic nanoparticles are exposed to a magnetic field or radiation oscillating at the high frequency and at the medium and/or low frequency.

In another embodiment of the invention, a magnetic hyperthermia diagnosis method is a method of diagnostic, preferentially used to detect an illness, or a condition, most preferentially by detection of a substance of interest, which can be comprised in the body part of the individual. It can be a method of detection in which: i), the substance of interest is initially bound to the magnetic nanoparticles and then detaches from them under application of the oscillating magnetic field or radiation or ii), the substance of interest is initially detached from the nanoparticles and then binds to them under application of the oscillating magnetic field or radiation, or iii), the type of interaction between the substance of interest and the magnetic nanoparticles changes under application of the oscillating magnetic field or radiation. Such change may then be used to detect the substance of interest.

The present invention concerns magnetic nanoparticles for use in a magnetic hyperthermia cosmetic method, wherein the magnetic nanoparticles are exposed to a magnetic field or radiation oscillating at the high frequency and, at the medium frequency and/or at the low frequency.

In another embodiment of the invention, a magnetic hyperthermia cosmetic method is a cosmetic method, preferentially a method used to make the body part of the individual, such as the skin, hair, or face, more appealing, more beautiful, to cover or hide a defect or deficiency of the body part of the individual, to improve the appearance of defect or irregularity of the body part of the individual. It can be a cosmetic method in which magnetic nanoparticles exposed to the oscillating magnetic field or radiation change the color, the appearance, the cell distribution, the tension, of the body part of the individual.

The present invention concerns magnetic nanoparticles for use in a magnetic hyperthermia vaccination or prophylactic method, wherein the magnetic nanoparticles are exposed to a magnetic field or radiation oscillating at the high frequency and at the medium and/or low frequency.

In still another embodiment of the invention, a magnetic hyperthermia prophylactic or vaccination method is a method that stimulates the immune system to fight against an illness such as a tumor, where the stimulation of the immune system can preferentially be repeated by applying the oscillating magnetic field or radiation more than once, most preferentially by applying this field in the presence of the magnetic nanoparticle in the body part of the individual. The vaccination or prophylactic method can be undertaken before or after the illness has occurred and be repeated, started by the administration of the magnetic nanoparticle, preferentially in the body part of the individual, be activated by the application of the oscillating magnetic field or radiation, preferentially be re-activated by re-applying the oscillating magnetic field or radiation, most preferentially without re-administering the nanoparticles. In some cases, this vaccination or prophylactic method enables to boost the activity of the immune system by applying the oscillating magnetic field or radiation and should preferentially be more efficient than a standard vaccination or prophylactic method, for which a control over the activity of the immune system can hardly be achieved.

In one embodiment of the invention, the nanoparticles are administered directly into the body part of the individual, for example by intra-tumor injection.

In another embodiment of the invention, the nanoparticles are administered indirectly in the body part of the individual, for example by intravenous injection, or at a distance from the body part of the individual, which is larger than 1 cm, 10 cm, 100 cm, 1 m, or 2 m.

In one embodiment of the invention, the concentration of magnetic nanoparticle is sufficient in the body part of the individual to enable a temperature increase therein, i.e. this concentration is larger than 1 ng, 10 ng, 100 ng, 1 μg, 10 μg, 100 μg, 1 mg, 10 mg, 100 mg, 1 g, 10 g, 100 g, or 1 kg per mm³ of the body part of the individual.

In one embodiment of the invention, the magnetic nanoparticles occupy a high enough percentage of the body part of the individual to induce a temperature increase in such part, i.e. this percentage is higher or larger than 10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 15, 25, 50, or 75% in such part, where this percentage may represent the volume occupied by the nanoparticles in such part divided by the total volume of such part.

The invention also concerns magnetic nanoparticles, wherein the magnetic nanoparticles have a SAR higher or larger than 1 W/g_(Fe), or than 0.001, 0.1, 1, 10, 50, 100, 500, 750, 1000, 2000, or 5000 Watt per gram of nanoparticles (W/g), preferentially Watt per gram of iron comprised in nanoparticles (W/g_(Fe)).

In another embodiment of the invention, the magnetic nanoparticles possess a SAR, which is sufficient to induce a temperature increase, i.e. a SAR, which is larger than 0.001, 0.1, 1, 10, 50, 100, 500, 750, 1000, 2000, or 5000 Watt per gram of nanoparticles (W/g), preferentially Watt per gram of iron comprised in nanoparticles (W/g_(Fe)).

In still another embodiment of the invention, the oscillating magnetic field or radiation is sufficiently powerful to induce a temperature increase, i.e. it has a power of more than 10⁻¹⁰, 10⁻⁵, 10⁻², 10⁻¹, 1, 10, 10², or 10³ Watt per cm³ of exposed body part.

In still another embodiment of the invention, the SAR is measured in at least one of the following conditions : (i), at a nanoparticle concentration that is sufficiently high so that the SAR does not vary as a function of nanoparticle concentration, or at a concentration that is larger than 0.01, 0.1, 1, 2, 5, 10, 20, 30, 40, or 50 mg/ml, (ii), in a liquid medium such as water or in a solid medium or in a semi solid medium such as a gel, (iii), by applying an oscillating magnetic field or radiation with an amplitude or maximum or average magnetic field or radiation larger than 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 75, or 100 mT, (iv), by applying an oscillating magnetic field or radiation with a frequency or high frequency higher or larger than 1, 2, 5, 10, 25, 50, 100, 200, 500, or 1000 kHz, (v), in a volume that is smaller than 1000, 500, 250, 100, 50, 20, 10, 5, 2, or 1 μ1, (vi), in a volume that is larger than 1000, 500, 250, 100, 50, 20, 10, 5, 2, or 1 μ1, or (vii), in adiabatic conditions, preferentially in conditions where heat losses are lower than 10, 5, 2, 1, 0,1, or 0.01° C. in the container or tube comprising the nanoparticles and used for SAR measurement.

In one embodiment of the invention, the magnetic nanoparticle is characterized by at least one of the following properties: i), a composition comprising at least one transition metal, preferentially an oxide of a transition metal, most preferentially iron oxide, most preferentially maghemite or magnetite, or an intermediate composition between maghemite and magnetite, where this composition may preferentially be that of the magnetic core of magnetic nanoparticles, ii), the presence of a coating that surrounds the magnetic core of the nanoparticles and prevents nanoparticle aggregation, preferentially enabling nanoparticle administration in an organism or stabilizing the nanoparticle magnetic core, where coating thickness may preferably lie between 0.1 nm and 10 μm, 0.1 nm and 1 μm, 0.1 nm and 100 nm, 0.1 nm and 10 nm, or between 1 nm and 5 nm, iii), a diamagnetic, paramagnetic, superparamagnetic, ferromagnetic, or ferrimagnetic behavior, where this behavior is preferably measured or observed at a temperature larger than 1 K, 10 K, 20 K, 50 K , 100 K, 200 K, 300 K, or 350 K, iv), a coercivity larger than 0.01, 0.1, 1, 10, or 100 Oe, a ratio between remanent and saturation magnetization larger than 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, or 0.75, or a saturation magnetization larger than 0.1, 1, 5, 10, or 50 emu/g, where these properties are preferably measured or observed at a temperature larger than 1 K, 10 K, 20 K, 50 K, 100 K, 200 K, 300 K, or 350 K, v), a crystallinity, i.e. nanoparticles have at least 2, 5, 10, or 100 crystalline planes, preferentially observable by electron microscopy, vi), the presence of a single domain, vii), a size that is are larger than 0.1, 0.5, 1.5, 10, 15, 20, 25, 30, 50, 60, 70, 80, 100, 120, 150, or 200 nm, viii), a size that is smaller than 0.1, 0.5, 1.5, 10, 15, 20, 25, 30, 50, 60, 70, 80, 100, 120, 150, or 200 nm, ix), a size between 0.1 nm and 10 μm, 0.1 nm and 1 μm, 0.1 nm and 100 nm, 1 nm and 100 nm, or between 5 nm and 80 nm, x), a nonpyrogenicity, i.e. nanoparticles possess an endotoxin concentration lower than 10000, 1000, 100, 50, 10, 5, 2, or 1 EU (endotoxin unit) per mg of nanoparticle or per mg of iron comprised in nanoparticles, xi), a synthesis method that is chemical, i.e. without the involvement of a living synthetizing organism, xii), a synthesis by a synthetizing living organism, preferentially by magnetotactic bacteria, leading to the production of magnetosomes, preferentially extracted from magnetotactic bacteria, preferentially only or mostly comprising the mineral magnetic core of the magnetosomes, xiii), the presence of less than 50, 25, 15, 10, 5, 2, or 1% of organic or carbon material originating from the synthetizing living organism, xiv), the presence of more than 99, 95, 80, 70, 60, 50, or 25% of mineral magnetic material originating from the synthetizing living organism.

In one embodiment of the invention, the SAR of the magnetic nanoparticle possessing one of the above property is 1.1, 1.2, 1.5, 2, 5, 10, 15, 20, 50, or 100 larger than the SAR of the magnetic nanoparticle without this property, or is larger than 10, 20, 50, 100, 1000 W/g_(Fe), where the SAR is preferentially measured at high nanoparticle concentration, or at a concentration larger than 1, 10, or 100 mg/mL.

In one embodiment of the invention, the magnetic nanoparticle possessing one of the above property has a SAR, which increases, preferentially by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 100, or 1000, with increasing ratio between maximum and average magnetic field or radiation, preferentially by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 100, or 1000. In some cases, the SAR of the magnetic nanoparticle with one of the above property increases more than a magnetic nanoparticle without such property.

In another embodiment of the invention, a high ratio between maximum and average magnetic field or radiation, preferentially larger than 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 4, 5, 10, 25, 50, 100, or 1000, corresponds to the application of an oscillating magnetic field or radiation with a high amplitude, preferentially larger than 0.1, 1, 2, 5, 10, 15, 25, 50, 100, 250, or 500 mT, applied during a short period of time, preferentially during a time of less than 1 day, 1 hour, 30, 15, 5, 2, or 1 minute, 50, 30, 20, 10, 5, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10⁻⁹, 10⁻¹⁰, 10⁻¹¹, 10⁻¹², 10⁻¹³, 10⁻¹⁴, or 10⁻¹⁵ seconds.

In still another embodiment of the invention, the high ratio enhances the coupling between the magnetic moment of the magnetic nanoparticle and the oscillating magnetic field or radiation, where this enhancement is preferentially more pronounced for nanoparticles with such property than for those without such property.

The invention also concerns magnetic nanoparticles for use, in which the high frequency is between 1 and 10 000 kHz.

The invention also relates to magnetic nanoparticles for use, in which the high frequency is between 1 and 1000 kHz.

In one embodiment of the invention, the high frequency f_(h) is larger than 10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, or 10⁸ kHz, or is between 10⁻¹⁰ and 10⁸ kHz, or between 10⁻⁵ and 10⁵ kHz, or between 10⁻³ and 10³ kHz, where this frequency may be equal or proportional to [2π/t₁], [1/t₁], [/2π/t₂], [1/t₂], [2π/t₃], [1/t₃], [2π/(t₁−t₂)], [1/(t₁+t₂)], [2π/(t₁+t₃)], [1/(t₁+t₃)], [2π/(t₂+t₃)], [1/(t₂+t₃)], [2π/(t₁+t₂+t₃)], or [1/(t₁+t₂+t₃)].

In another embodiment of the invention, [t₁/t₂], [t₁/t₃] or [t₂/t₃], is lower than or equal to 10⁻¹⁰, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10², 10³, 10⁵, or 10¹⁰.

In an embodiment of the invention, the measurement time used to measure one or several high frequency or frequencies of oscillation is the time during which the variation of the amplitude or strength of the magnetic field or radiation is measured. This time is preferentially sufficiently long, but not too long, to be able to observe more than 1, 2, 5, 10, 100, or 1000 oscillation(s).

In another embodiment of the invention, the measurement time used to measure the high frequency oscillation lies between 10⁻⁶ and 10⁻⁴ seconds, between 10⁻⁷ and 10⁻³ seconds, between 10⁻⁸ and 10⁻¹ seconds, between 10⁻⁹ and 1 second.

In still another embodiment of the invention, the measurement time used to measure the high frequency oscillation is larger than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, or 1 second.

In still another embodiment of the invention, the measurement time used to measure the high frequency oscillation is smaller than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, or 1 second.

In another embodiment of the invention, the time of application of the magnetic field or radiation oscillating at high frequency, f_(h), is sufficiently large and/or the period associated to the high frequency of oscillation, T_(h)=1/f_(h), is sufficiently short, so that the high frequency of oscillation does not lead to any temperature decrease, or leads to a temperature decrease of less than 10, 5, 1° C., when a suspension of magnetic nanoparticles, preferentially at a concentration larger than 0.1, 1, or 10 mg/mL, is exposed to this magnetic field or radiation. The sole application of the high frequency is preferentially not sufficient to induce cooling steps. This is the reason why it may be necessary to add a low frequency of oscillation to produce cooling steps.

The invention also concerns magnetic nanoparticles for use, wherein the high frequency heats the magnetic nanoparticles.

In one embodiment of the invention, the high frequency of oscillation induces a movement, preferably a rotation, a translation, or a vibration of the nanoparticles, preferentially in the body part of the individual. This movement may be responsible for heating the nanoparticles.

In another embodiment of the invention, the high frequency of oscillation induces a rotation of the magnetic moment of the magnetic nanoparticle. This rotation can be responsible for heating the nanoparticles. The rotation of the magnetic moment can take place alone or in conjunction with the movement of the nanoparticles.

In another embodiment of the invention, the high, medium, and/or low frequency of oscillation does not induce any movement, rotation, translation, or vibration of the nanoparticles, preferentially in the body part of the individual.

In another embodiment of the invention, the high frequency of oscillation is kept sufficiently low, for example to limit undesirable effects, such as Eddy or Foucault currents or other potential toxic effects which may occur at this frequency, i.e. preferentially lower than 1000, 500, 250, 150, 100, 50, 20, 10, 5, or 1 kHz.

In another embodiment of the invention, the high frequency of oscillation enables to heat magnetic nanoparticles without the production of Eddy or Foucault currents.

In still another embodiment of the invention, the high frequency of oscillation enables to heat the magnetic nanoparticles with the production of Eddy or Foucault currents, where the production of such current is preferentially kept sufficiently low to avoid a temperature increase of the body part of the individual exposed to the oscillating magnetic field or radiation of more than 0.0001, 0.001, 0.01, 0.1, 1, 2, 5, 10, 20, 50, or 100° C.

In another embodiment of the invention, Eddy or Foucault currents are defined as the heat produced under the application of the oscillating magnetic field or radiation by materials, substances, compounds, tissues, cells, or the part of the body part of the individual, which are different from magnetic nanoparticles. Eddy or Foucault currents preferentially occur in region without magnetic nanoparticles or comprising a small concentration of magnetic nanoparticles, preferentially less than 10⁹, 10⁶, 10³, 10, 1, 10⁻¹, 10⁻³, 10⁻⁶, or 10⁻⁹ mg of nanoparticles per mm³ of substance, compound, tissue, cell, or the body part of the individual.

In another embodiment of the invention, Eddy or Foucault currents are defined as temperature increases under the application of the oscillating magnetic field or radiation, preferentially larger than 0.01, 0.1, 1, 5, 10, or 20° C., preferentially not due to the production of heat by magnetic nanoparticles.

In another embodiment of the invention, Eddy or Foucault currents occur when maximum or average magnetic field or radiation is high, preferentially higher or larger than 0.1, 0.5, 1, 5, 10, 20, 50, 100, or 200 mT. In some cases, using oscillating magnetic field or radiations with low maximum or average magnetic field or radiation, preferentially lower than 0.1, 0.5, 1, 5, 10, 20, 50, 100, or 200 mT, enables to reduce Eddy or Foucault currents.

In another embodiment of the invention, Eddy or Foucault currents occur when the high oscillation frequency is high, preferentially higher or larger than 0.1, 1, 10, 100, or 1000 kHz.

In still another embodiment of the invention, Eddy or Foucault currents occur when the volume exposed to the oscillating magnetic field or radiation is larger than 1, 10, 10², 10³, 10⁶, 10⁹, or 10¹⁵ mm³. In some cases, using a low volume exposed to the oscillating magnetic, preferentially lower than 1, 10, 10², 10³, 10⁶, 10⁹, or 10¹⁵ mm³, enables to reduce Eddy or Foucault currents.

In another embodiment of the invention, the high frequency of oscillation is kept sufficiently high, for example to be able to heat the nanoparticles or to avoid undesirable effects that may occur at a too low high frequency such as undesired cellular or muscular stimulations, i.e. preferentially larger than 1, 5, 20, 100, 150, 250, 500, or 1000 kHz.

In one embodiment of the invention, to lower the high frequency of oscillation, preferentially below 10⁶, 10³, or 10 kHz, nanoparticle concentration is increased, i.e. nanoparticle concentration is larger than 0.01, 0.1, 1, 10, 20, 50, 10², 10³, 10⁶ or 10⁹ μg of nanoparticles per mm³ of the body part of the individual, or per mm³.

In one embodiment of the invention, to lower the high frequency of oscillation, preferentially below 10⁶, 10³, or 10 kHz, nanoparticle homogeneity of distribution is increased, i.e. nanoparticles occupy more than 5, 10, 25, 50, 75, 80, 85, 90, 95, 98, 100, 150, 200, 500, 10³, or 10⁵% of the part of the body part of the individual, where this percentage may represent the volume occupied by the nanoparticles divided by the volume of the body part of the individual. In some cases, the homogeneity of nanoparticle distribution can be increased by using nanoparticles that possess more homogenous distribution, such as nanoparticles or magnetosomes organized in chains, or by using an administration technique that enables to increase homogenous distribution, such as an administration carried out at a flow rate or speed, which is lower than 10⁹, 10⁵, 10³, 10², 10, 1 mg of nanoparticles administered to the body part per minute of injection.

In another embodiment of the invention, to lower the high frequency of oscillation, preferentially below 10⁶, 10³, or 10 kHz, nanoparticles with high SAR are used, i.e. nanoparticles with SAR preferentially larger than 1, 5, 10, 20, 50, 100, 200, 500, or 1000 W/g. Such nanoparticles may be nanoparticles of large sizes, i.e. of sizes larger than 1, 5, 10, 20, 50, 75, 90, or 100 nm, or monodomain nanoparticles, or ferromagnetic, or ferromagnetic nanoparticles. Such nanoparticles may also distribute homogeneously in the tissues to enable a homogeneous distribution of the temperature. They may be arranged in chains, such as magnetosomes produced by magnetotactic bacteria, which are preferably extracted from these bacteria and purified to remove toxic bacterial residues such as endotoxins. The chain arrangement may yield homogeneous heating and high SAR, preferentially higher or larger than 100, 250, 500, or 1000 W/g.

In another embodiment of the invention, to lower the high frequency of oscillation, preferentially below 10⁶, 10³, or 10 kHz, maximum or average magnetic field or radiation can be increased above 1, 2, 5, 10, 15, 20, 25, 30, 40, 50, 75, 100, 250, 500, or 1000 mT.

The invention also relates to magnetic nanoparticles for use, wherein the medium frequency lies between 10⁻⁵ and 10⁶ Hz.

The invention also relates to magnetic nanoparticles for use, wherein the medium frequency is lower than the high frequency and lies between 10⁻⁵ and 5.10⁵ Hz.

In one embodiment of the invention, the medium oscillation frequency is larger than 10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, or 10⁸ Hz.

In one embodiment of the invention, the medium oscillation frequency is smaller than 10⁻¹⁰, 10⁻⁹, 10⁻⁸, 10⁻, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, or 10⁸ Hz.

In another embodiment of the invention, the medium oscillation frequency lies between 10⁻²⁰ and 10²⁰ Hz, 10⁻¹⁰ and 10¹⁰ Hz, 10⁻⁸ and 10⁸ Hz, 10⁻⁶ and 10⁶ Hz, 10⁻⁵ and 10⁵ Hz, 10⁻⁴ and 10⁴ Hz, or between 10⁻³ and 10³ Hz.

In one embodiment of the invention, the medium frequency of oscillation is 1.001, 1.01, 1.1, 2, 5, 10, 10², 10³, 10⁴, 10⁵, or 10¹⁰ times lower than the high frequency of oscillation.

In one embodiment of the invention, the medium frequency of oscillation takes place in at least 1, 2, 5, 10, 10², 10³, 10⁵, 10¹⁰, 10²⁰, or 10⁵° cycles.

In an embodiment of the invention, the measurement time used to measure the medium frequency of oscillation is the time during which the variation of the amplitude or strength of the magnetic field or radiation is measured. This time is preferentially sufficiently long, but not too long, to be able to observe more than 1, 2, 5, 10, 100, or 1000 medium frequency oscillations.

In another embodiment of the invention, the measurement time used to measure the medium frequency oscillation lies between 10⁻⁶ and 10⁻⁴ seconds, between 10⁻⁷ and 10⁻³ seconds, between 10⁻⁸ and 10⁻¹ seconds, between 10⁻⁹ and 1 second.

In still another embodiment of the invention, the measurement time used to measure the medium frequency oscillation is larger than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², or 10³ second.

In still another embodiment of the invention, the measurement time used to measure the medium frequency oscillation is smaller than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², or 10³ second.

In still another embodiment of the invention, the measurement time used to measure the medium frequency of oscillation is 1.001, 1.01, 1.1, 1.5, 2, 5, 10, 100, 1000, or 10000 longer than measurement time used to measure the high frequency of oscillation.

In still another embodiment of the invention, the medium frequency of oscillation is too high, and/or the time t₅ is too short, to enable a decrease in temperature of the magnetic nanoparticles or of their surroundings, preferentially to yield a temperature decrease of more than 1, 5, 10, 50, or 100° C., when a suspension of magnetic nanoparticles, preferentially at a concentration of more than 0.1, 1, or 10 mg/mL, is exposed to this magnetic field or radiation, where temperature is measured between at least 1, 10, 100, or 1000 high frequency oscillations. The fact that the medium frequency of oscillation can't result in temperature decrease can be problematic in a magnetic hyperthermia treatment, since it can possibly lead to Eddy or Foucault currents or to other side effects due to continuous heating, possibly leading to overheating. This is the reason why it may appear necessary to add a low frequency of oscillation that enables cooling steps.

The invention also concerns magnetic nanoparticles for use, wherein the medium frequency modulates the high frequency.

In one embodiment of the invention, the modulation of the high frequency of oscillation by the medium frequency of oscillation corresponds to a magnetic field or radiation oscillating at a high frequency within an envelope function oscillating at a medium frequency.

In one embodiment of the invention, the purpose of the envelope function may be to reach higher or larger maximum or average magnetic field or radiations than those reached without the envelope function, of maximum or average magnetic field or radiations preferentially larger than 1, 5, 10, 50, 100, 500, or 1000 mT, preferentially reached during short times, most preferentially during less than 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, or 10⁻⁶ seconds, or most preferentially during less than 80, 70, 50, 20, 10, 5, or 1% of the duration of one medium frequency cycle.

In one embodiment of the invention, the purpose of the envelope function may also be to reach magnetic field or radiations with maximum or average magnetic field or radiation larger than 1, 10, 100, 500, or 1000 mT, or with maximum or average magnetic field or radiation higher or larger, preferentially 1.01, 1.1, 1.2, 2, 5, 10, 20, 30, 50, or 100 times higher or larger, than that reached by a magnetic field or radiation oscillating at the high frequency without the envelope function.

In one embodiment of the invention, the high maximum or average magnetic field or radiation produced by the modulation occurs preferentially within part of a cycle associated to a medium frequency, preferentially within less than 90, 80, 75, 50, 25, 15, 10, 5, 2, or 1% of this cycle.

The invention also concerns magnetic nanoparticles for use, wherein the medium frequency leads to increased heating properties of the magnetic nanoparticles.

The invention also relates to magnetic nanoparticles for use according to the invention, wherein the low frequency is lower than the high frequency and the medium frequency when it is present and lies between 10⁻⁹ and 5.10⁵ Hz.

In an embodiment of the invention, the low frequency lies between 10⁻¹⁵ and 10¹⁵ Hz, between 10⁻¹² and 10¹² Hz, between 10⁻⁹ and 10⁹ Hz, between 10⁻⁹ and 10⁵ Hz, between 10⁻⁶ and 10⁵ Hz, between 10⁻³ and 10³ Hz. In some cases, the low frequency can be lower than 10⁻¹⁵, 10⁻¹², 10⁻⁹, 10⁻⁷, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10³, 10⁵, 10⁷, 10⁹, 10¹², or 10¹⁵ Hz. In some cases, the low frequency can be larger than 10⁻¹⁵, 10⁻¹², 10⁻⁹, 10⁻⁷, 10⁻⁵, 10⁻³, 10⁻¹, 1, 10, 10³, 10⁵, 10⁷, 10⁹, 10¹², or 10¹⁵ Hz.

In one embodiment of the invention, the medium frequency increases nanoparticle heating power, i.e. it increases nanoparticle SAR by a factor of more than 1.00001, 1.0001, 1.001, 1.01, 1,1, 1,2, 1,5, 2, 5, 10, 10², or 10³ times the SAR of the same nanoparticles, measured with a magnetic field or radiation oscillating without the medium frequency.

In still another embodiment of the invention, the medium frequency of oscillation leads to a high nanoparticle heating power, i.e. it enables to reach SAR values of more than 1, 10, 100, 250, 500, or 1000 W/g_(Fe).

The invention also concerns magnetic nanoparticles for use, in which the low frequency induces at least one cycle comprising a heating step and a cooling step.

In one embodiment of the invention, the heating step is triggered by the application of the oscillating magnetic field or radiation, preferably in a region containing a sufficiently high concentration of magnetic nanoparticles to induce heating.

In one embodiment of the invention, the heating step lasts at least 1 μs, 10 μs, 100 μs, 1 ms, 10 ms, 100 ms, 1 s, 10 s, or 100 s (seconds). In this case, it can take place when the low frequency of oscillation is lower than 10⁶, 10⁵, 10⁴, 10³, 10², 10, 1, 10⁻¹, or 10⁻² Hz, and preferentially the high frequency of oscillation is larger than 0.1, 1, 10, 100, 200, 500, 10³, 10⁴, or 10⁵ kHz. The heating step can last longer when nanoparticles are less concentrated in the body part of the individual or have diffused outside of the body part of the individual, where such diffusion can take place 1, 2, 6, or 12 hours, 1, 2, or 7 days, 1, 2, or 4 weeks, 1, 2, or 6 months, 1, 2, or 10 years, following nanoparticle administration.

In another embodiment of the invention, the heating step lasts less than 1 μs, 10 μs, 100 μs, 1 ms, 10 ms, 100 ms, 1 s, 10 s, or 100, seconds, 5, 10, 20, or 30 minutes. In this case, it can take place when the low oscillation frequency is lower than 10⁶, 10⁵, 10⁴, 10³, 10², 10, 1, 10⁻¹, or 10⁻² Hz, and the high oscillation frequency is preferentially larger than 0.1, 1, 10, 100, 200, 500, 10³, 10⁴, or 10⁵ kHz. The heating step may take less time when the magnetic nanoparticles have not diffused outside of the body part of the individual, preferentially during a time, which is less than 1, 2, 6, or 12 hours, 1, 2, or 7 days, 1, 2, or 4 weeks, 1, 2, or 6 months, 1, 2, or 10 years, depending on nanoparticle administration route.

In one embodiment of the invention, the duration of the heating step is as short as possible to limit Eddy or Foucault currents or undesirable or toxic effects associated with the application of the oscillating field over a long period of time.

In one embodiment of the invention, the heating step takes place during the time necessary to reach a temperature obtained during a hyperthermia session or treatment, or a temperature obtained during a thermoablation session or treatment, or a temperature above 37, 48, 49, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 10³, 10⁵, or 10¹⁰° C., or a temperature between 37 and 1000° C., 37 and 100° C., 37 and 70° C., 37 and 55° C., 37 and 50° C., or between 37 and 45° C. In another embodiment of the invention, the heating time t₇ or t₉ is sufficiently long to induce the temperature increase.

According to the invention, the temperature increase can be larger than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 , 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 85, 90, 100, 250, 500, or 10³° C., or ° C. per second, or ° C. per hour, where this temperature increase preferentially represents a temperature increase above physiological temperature.

According to the invention, the temperature increase can be smaller than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 , 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 85, 90, 100, 250, 500, or 10³° C., or ° C. per second, or ° C. per hour, where this temperature increase preferentially represents a temperature increase above physiological temperature.

In another embodiment of the invention, the heating time t₇ or t₉ is sufficiently long or the low frequency is sufficiently small to reach a temperature plateau. Such a plateau can be achieved when the temperature increase is less than 1° C. per day, 1° C. per minute, 1° C. per second, or 1° C. per microsecond, or when the temperature increase is 10⁴, 10³, 10², 10, 5, or 2 times lower than the initial temperature increase, measured at the beginning of the heating step, preferentially during the 100, 10, 1, 0.1, or 0.01 seconds following the switching on of the magnetic field or radiation or of the device generating the magnetic field or radiation.

In an embodiment of the invention, the heating time t₇ or t₉ can be reduced by increasing the maximum or average magnetic field or radiation, and/or high frequency. It is thus preferable to apply an oscillating magnetic field or radiation with a maximum or average magnetic field or radiation larger than 0.01, 0.1, 1, 5, 10, 20, 40 mT and/or high oscillation frequency larger than 0.1, 100, 200, 500, 10³, 10⁴, or 10⁵ kHz, to yield a heating time t₇ or t₉, which is lower than 1 μs, 10 μs, 100 μs, 1 ms, 10 ms, 100 ms, 1 s, 10 s, or 100 seconds.

In one embodiment of the invention, to decrease the nanoparticle heating time t₇ or t₉, nanoparticle SAR is increased, preferentially above 1, 10, 25, 50, 100, 250, 500, or 1000 W/g, or the power of the oscillating magnetic field or radiation is increased above 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², or 10³ Watt per cm³ of body part and/or nanoparticle homogeneity of distribution is increased in the body part of the individual.

In an embodiment of the invention, the heating time t₇ or t₉ increases when the maximum or average magnetic field or radiation and/or high oscillation frequency decrease(s). It can thus be preferred to apply an oscillating magnetic field or radiation with a maximum or average magnetic field or radiation, which is lower than 0.01, 0.1, 1, 5, 10, 20, or 40 mT and/or a high oscillation frequency, which is lower than 0.1, 1, 10, 100, 200, 500, 10³, 10⁴, or 10⁵ kHz, to achieve a heating step that lasts longer than 1 μs, 10 μs, 100 μs, 1 ms, 10 ms, 100 ms, 1 s, 10 s or 100 s (seconds).

In an embodiment of the invention, the cooling time t₈ or t₁₀ is shorter than 1 day, 12, 4, 2, or 1 hour, 60, 30, 20, 2, or 1 minute, 40, 30, or 20 seconds.

In another embodiment of the invention, the cooling time t₈ or t₁₀ is independent of nanoparticle concentration.

In still another embodiment of the invention, low frequency cycles are associated with cooling times t₈ or t₉ shorter than 1 day, 12, 4, 2, or 1 hour, 60, 30, 20, 2, or 1 minute, 40, 30, or 20 seconds, and/or with heating times t₇ or t₁₀ shorter than 1 day, 12, 4, 2, or 1 hour, 60, 30, 20, 2, or 1 minute, 40, 30, or 20 seconds.

In some cases, it may be preferable to favor short heating and/or cooling steps, preferentially if it is desired to induce a large number of temperature gradients. This may be the case if one wishes to trigger certain mechanisms, such as an immune mechanism, preferably a mechanism involved in pathological or tumor cell destruction.

In other cases, it may be preferable to favor long heating and/or cooling steps, preferentially if it is desired to keep the temperature constant over a long period of time. This may be the case if one wishes to destroy cells using constant temperatures during a long period.

In an embodiment of the invention, the measurement time used to measure one or several frequencies of oscillation is the time during which the variation of the amplitude or strength of the magnetic field or radiation is measured, or the time during which the variation of the power of the oscillating magnetic field or radiation is measured. This time is preferentially sufficiently long, but not too long, to be able to observe more than 1, 2, 5, 10, 100, or 1000 low frequency of oscillation.

In another embodiment of the invention, the measurement time used to measure the low frequency oscillation lies between 10⁻⁶ and 10⁴ seconds, between 10⁻³ and 10³ seconds, between 10⁻¹ and 10³ seconds, between 1 and 100 second.

In still another embodiment of the invention, the measurement time used to measure the low frequency oscillation is larger than 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, or 10⁴ seconds.

In still another embodiment of the invention, the measurement time used to measure the low frequency oscillation is smaller than 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, or 10⁴ seconds.

The invention also concerns magnetic nanoparticles for use, wherein the heating step produces a temperature increase of more than 1° C. of the body part.

In one embodiment of the invention, the heating step leads to a temperature increase of more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 , 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 85, 90, 100, 250, 500, or 10³° C., or ° C. per second, or ° C. per hour, preferentially of the body part. This temperature increase can be measured between the beginning of magnetic field or radiation application and the time when magnetic field or radiation application is stopped. This increase in temperature may correspond to an increase in temperature above the physiological temperature.

In one embodiment, the physiological temperature may be the temperature of the body part of the individual, preferentially measured when this individual is in its normal condition. According to the invention, physiological temperature may be 37° C., or between 36.1 and 37.8° C.

In another embodiment of the invention, the increase in temperature is an increase in temperature of the body part of the individual, preferentially containing a concentration in magnetic nanoparticles larger than 1 ng, or 10 ng, or 100 ng, or 1 μg, or 10 μg, or 100 μg, or 1 mg, or 10 mg, or 100 mg per mm³, or per mm³ of the body part of the individual. In another embodiment of the invention, temperature increase is caused by applying an oscillating magnetic field or radiation at one or more than one high oscillation frequency, preferentially larger than 10, 50, 100, 250, 500, or 1000 kHz.

In still another embodiment of the invention, temperature increase is caused by applying an oscillating magnetic field or radiation of power larger than 10⁻¹⁵, 10⁻⁹, 10⁻⁵, 10⁻², 1, 10, 10², 10³, or 10⁵ Watt per cm³ of body part.

In one embodiment of the invention, the increase in temperature occurs selectively in the body part of the individual. This may be possible when nanoparticles are in sufficient concentration in the body part of the individual, i.e. at a concentration, which is larger than 1 ng, or 100 ng, or 100 μg, or 1 μg, or 10 μg, or 100 μg, or 1 mg, or 10 mg, or 100 mg per mm³, or per mm³ of the body part of the individual and the magnetic field or radiation is applied, preferentially selectively to the body part of the individual, preferentially the magnetic field or radiation is applied with a high frequency larger than 10, 50, 100, 250, 500, or 1000 kHz.

In an embodiment, the heating step is associated with an active temperature increase, i.e. a temperature increase preferentially due to magnetic nanoparticles being exposed to the oscillating magnetic field or radiation.

The invention also concerns magnetic nanoparticles for use, wherein the cooling step induces a temperature decrease of more than 1° C. of the body part.

In one embodiment of the invention, the cooling step produces a temperature decrease of more than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 85, 90, 100, 250, 500, or 10³° C., or ° C. per second, or ° C. per hour, preferentially of the body part. This decrease can be measured between the end of the A₇ or A₉ low frequency sequence, preferentially when magnetic field or radiation application is stopped, and the time when physiological temperature is reached or a temperature above physiological temperature by 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 80, 85, 90, 100, 250, 500, or 10³° C., is reached.

In one embodiment of the invention, the cooling step may be accelerated by using an apparatus, a refrigerant, an ice cube, a chemical, or a substance, which cools down the body part of the individual or the magnetic nanoparticle.

In another embodiment of the invention, the amplitude of temperature decrease of the cooling step does not differ by more than a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10², or 10³, from the amplitude of temperature increase of the heating step. This may preferentially be used when one wants to take advantage of both heating and cooling steps on the therapeutic effect.

In still another embodiment of the invention, the amplitude of temperature decrease of the cooling step differs by more than a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10², or 10³, from the amplitude of temperature increase of the heating step. This may preferentially be used when one wants to take advantage of either the heating or the cooling step on the therapeutic effect.

The invention also concerns magnetic nanoparticles for use, wherein the low frequency of oscillation enables to limit undesirable effects.

In an embodiment of the invention, the creation of cycles with heating and cooling steps enables to limit toxicity. First, the average temperatures reached using these steps are lower, preferentially by more than 1, 2, 3, 4, 5, 7, 10, 20, 50, 100, 500, or 1000° C., than those reached without these steps. Second overheating, preferentially due to Eddy or Foucault currents, can be avoided since the body part of the individual can be cooled down or remain without any temperature increase during the cooling steps.

According to the invention, a low frequency can yield a number of heating and/or cooling steps or a number of heating and/or cooling gradients, which is 2, 3, 5, 10, 10², 10³, 10⁵, 10¹⁰, or 10²⁰ greater than the number of steps or gradients without the low frequency.

In an embodiment, the cooling step is associated with a passive temperature decrease, i.e. a temperature decrease which is preferentially due to the temperature decrease of the body part of the individual without application of a magnetic field or radiation, which can be due to blood circulation.

The invention also concerns magnetic nanoparticles for use, wherein the low frequency of oscillation enables to improve treatment or diagnosis efficacy, or enables to reach a more efficient treatment or diagnosis than without the low frequency.

In an embodiment of the invention, the low frequency of oscillation improves treatment or diagnosis efficacy by increasing the number of heating and cooling steps, preferentially the number of temperature gradients associated to each heating and cooling step, preferentially by producing more than 10⁹, 10⁷, 10⁵, 10³, 10, or 1 temperature gradient(s). Such gradients could more efficiently destroy pathological cells, for example by more efficiently activating the immune system or by more efficiently inducing a stress, preferentially a cellular stress, than a continuous heating, which is associated with a fewer number of temperature gradients, preferentially less than 10⁹, 10⁷, 10⁵, 10³, 10, or 1 temperature gradient(s). The invention also concerns magnetic nanoparticles for use, wherein the medium and/or low frequency of oscillation enable(s) to increase the ratio between maximum and average magnetic field or radiations.

In another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and medium and/or low frequency, enables to reach average magnetic field or radiations that are lower than 100, 50, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.1 mT, or that are lower than those reached without the medium and/or low frequency by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 20, 30, 50, or 100.

In another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and medium and/or low frequency, enables to reach maximum magnetic field or radiations that are larger than 100, 50, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0.1 mT, or that are larger than those reached without the medium and/or low frequency by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 20, 30, 50, or 100.

In still another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and medium and/or low frequency, enables to reach maximum magnetic field or radiations over a short period of time, preferentially less than 1 hour, 30, 15, 5, 2, or 1 minute, 30, 15, 10, 5, 2, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁴, 10⁻⁵, 10⁻⁶, 10⁻⁷, 10⁻⁸, 10⁻⁹, 10⁻¹⁰, 10⁻¹¹, 10⁻¹², 10⁻¹³, 10⁻¹⁴, or 10⁻¹⁵ seconds.

In still another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and, medium and/or low frequency, enables to reach maximum magnetic field or radiations over a shorter period of time, preferentially by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 20, 30, 50, or 100, compared with the magnetic field or radiation oscillating without the medium and/or low frequency.

In another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and, medium and/or low frequency, enables to increase the ratio between maximum and average magnetic field or radiations by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 20, 30, 50, or 100 compared with the same ratio measured without the medium and/or low frequency.

In still another embodiment of the invention, the application of the magnetic field or radiation, oscillating at high and, medium and/or low frequency, enables to reach a ratio between maximum and average magnetic field or radiations, which is larger than 1.00001, 1.0001, 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 50, 100, 250, 500, 10³, 10⁴, or 10⁶.

The invention also concerns magnetic nanoparticles for use, wherein the medium and/or low frequency of oscillation decrease magnetic nanoparticle diffusion outside of the body part.

In one embodiment of the invention, the medium and/or low frequency of oscillation enable to heat the body part or magnetic nanoparticle during a time, which is 2, 5, 10, or 100 times longer than without the medium and/or low frequency of oscillation.

In another embodiment of the invention, the medium and/or low frequency of oscillation enable to heat the body part or magnetic nanoparticle during more than 1 minute, 1 hour, 1 day, 1 week, 1 month, or 1 year, following nanoparticle administration.

The invention also relates to magnetic nanoparticles, wherein the medium and/or low frequency of oscillation increase the release of a compound from the magnetic nanoparticles.

In one embodiment of the invention, the compound is a fluorescent substance, a medical, therapeutic, diagnostic compound, a compound of interest for biological, chemical or physical research, a compound used for depollution, detection of a physicochemical disturbance such as temperature, or of a radiation.

In another embodiment of the invention, the release of the compound corresponds to the diffusion of the compound at some distance from the nanoparticles, preferentially at a distance larger than 10⁻¹⁵, 10⁻⁶, 10⁻³, 1, 10³, 10⁶, or 10⁹ meters from the nanoparticles.

In another embodiment of the invention, the release of the compound is increased when the quantity of released compound is multiplied by a factor of 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10³, 10⁵, 10⁷, or 10¹⁰, in the presence of the low and/or medium frequency compared with a situation where the low and/or medium frequency is/are missing.

In another embodiment of the invention, the release of the compound corresponds to the diffusion of the compound at some distance from the nanoparticles, preferentially at a distance smaller than 10⁻¹⁵, 10⁻⁶, 10⁻³, 1, 10³, 10⁶, or 10⁹ meters from the nanoparticles.

In another embodiment of the invention, the release of the compound is increased when the quantity of released compound is multiplied by a factor of 1.01, 1.1, 1.2, 1.5, 2, 5, 10, 10³, 10⁵, 10⁷, or 10¹⁰, in the presence of the low and/or medium frequency compared with a situation where the low and/or medium frequency is/are missing.

In still another embodiment of the invention, the release of the compound is increased when the quantity of compound released, preferentially measured more than 100, 10, 1, 10⁻¹, 10⁻³, or 10⁻⁶ minutes following the activation or switching on of the oscillating magnetic field or radiation, is multiplied by a factor of more than 1.1, 1.5, 2, 5, 10, 100, 10³, 10⁵, or 10⁹.

In still another embodiment of the invention, the release of the compound is increased when the quantity of compound released, preferentially measured more than 100, 10, 1, 10⁻¹, 10⁻³, or 10⁻⁶ minutes following the activation or switching on of the oscillating magnetic field or radiation, is multiplied by a factor of less than 1.1, 1.5, 2, 5, 10, 100, 10³, 10⁵, or 10⁹.

In still another embodiment of the invention, the release of the compound is increased when the quantity of compound initially released, measured less than 100, 10, 1, 10⁻¹, 10⁻³, or 10⁻⁶ minutes following the activation or switching on of the oscillating magnetic field or radiation, is multiplied by a factor of more than 1.1, 1.5, 2, 5, 10, 100, 10³, 10⁵, or 10⁹.

In still another embodiment of the invention, the release of the compound is increased when the quantity of compound initially released, measured less than 100, 10, 1, 10⁻¹, 10⁻³, or 10⁻⁶ minutes following the activation or switching on of the oscillating magnetic field or radiation, is multiplied by a factor of less than 1.1, 1.5, 2, 5, 10, 100, 10³, 10⁵, or 10⁹.

The invention also concerns magnetic nanoparticles for use, wherein the low frequency of oscillation enables to improve treatment efficacy against an infectious disease such as a cancer or tumor.

In one embodiment of the invention, the creation of cycles with heating and cooling steps enables to create at least 1, 2, 5, 10, 10², 10³, or 10⁵ temperature gradient(s) of more than 0.01, 0.1, 1, 2, 5, 10, 15, 30, 50, 100, 500, or 1000° C. or 1000° C. per second or 1000° C. per minute or 1000° C. per hour. These temperature gradients are preferentially those occurring at the beginning of the magnetic excitation, preferentially less than 10¹⁵, 10¹², 10⁹, 10⁵, 10³, 10², 10, 1, or 10⁻¹ seconds following the application of the oscillating magnetic field or radiation. These temperature gradients can be more efficient in the treatment of an infectious disease, preferentially in the destruction of a tumor, or enable to destroy at least 10, 10², 10³, 10⁶, or 10⁹ times more cells, preferentially tumor cells, than a constant temperature. Between the different cycles, temperature gradients preferentially do not vary by more than 10⁹, 10⁷, 10⁵, 10³, 100, 10, 1, 10⁻³, 10⁻⁵, 10⁻⁷, or 10⁻⁹%.

The invention also relates to magnetic nanoparticles exposed to the oscillating magnetic field or radiation for use according to the invention, comprising cycles with heating and cooling steps, wherein: i) the maximum and minimum temperatures to be reached during the heating and cooling steps, respectively, are determined, ii) at least one parameter of the magnetic field or radiation modulating the temperature is set at a first value to reach the maximum temperature during the heating step and then the at least one parameter is set at a second value to reach the minimum temperature during the cooling step, optionally iii) the heating and cooling times required to reach these two temperatures are measured, and optionally iv) the heating and cooling steps are repeated at least during the measured heating and cooling times.

The invention also relates to magnetic nanoparticles for use according to the invention, in which the magnetic field or radiation comprises or triggers cycles with heating and cooling steps, wherein: i) the maximum and minimum temperatures to be reached during the heating and cooling steps, respectively, are determined, ii) at least one parameter of the magnetic field or radiation modulating the temperature is set at a first value to reach the maximum temperature during the heating step and then the at least one parameter is set at a second value to reach the minimum temperature during the cooling step, optionally iii) the heating and cooling times required to reach these two temperatures are measured, and optionally iv) the heating and cooling steps are repeated at least during the measured heating and cooling times.

The invention also relates to magnetic nanoparticles, wherein the at least one parameter is selected from the group consisting of: average or maximum magnetic field or radiation amplitude, magnetic field or radiation strength, amplitude, frequency, spatial or temporal distribution of magnetic field or radiation lines.

In one embodiment of the invention, the at least one parameter is a parameter of the device generating the alternating magnetic field or radiation. It can be the strength, amplitude, frequency, power, or duration of application of the alternating current generating the alternating magnetic field or radiation.

In one embodiment of the invention, a pre-calibration curve is realized to determine the heating and cooling times, which are necessary to reach the maximum and minimum temperatures, respectively, preferentially reached during low frequency cycles. Such pre-calibration can be realized using magnetic nanoparticles, preferentially mixed in suspension, with cells or with tissue, using conditions that are preferentially as close as possible from those of the treatment, i.e. using for example similar nanoparticle concentration and/or nanoparticle environment than those of the treatment. In some cases, the pre-calibration curve can be realized directly in the individual, for example when it is possible to measure the temperature in the body part of the individual, for example by introducing a temperature probe in such part. The pre-calibration curve may in some cases be realized in the individual, for example during the first session of magnetic hyperthermia treatment. For pre-calibration, the magnetic nanoparticles or the body part of the individual are preferentially exposed to the magnetic field or radiation oscillating at the high and low frequency, or at the high, medium and low frequency. The parameter of the device, such as the alternating current, is preferentially set at a first value to reach an average or maximum magnetic field or radiation that leads to a maximum temperature, preferentially between 40 and 60° C., during the heating step and then the parameter of the device such as the alternating current is preferentially set at a second value to reach another average or maximum magnetic field or radiation that leads to a minimum temperature, preferentially between 30 and 40° C., most preferentially the physiological temperature, during the cooling step. The heating and cooling times required to reach these two temperatures may then be measured and the heating and cooling steps may be repeated, preferentially more than 1, 2, 5, 10, or 100 times. The first and second values of the alternating current may preferentially be constant to simplify the treatment. Indeed, varying such values during the heating and/or cooling step(s) of a magnetic hyperthermia treatment would probably necessitate the use of additional software, and it appears that this is unnecessary. At the end, values of heating and cooling times can be used as such for the treatment, or can be modified to take into account the different conditions used for pre-calibration and for treatment such as differences in nanoparticle distribution, or can be averaged and average heating and cooling times may then be used for the treatment.

In one embodiment of the invention, the maximal temperature, T_(max), and minimal temperature, T_(min), preferentially reached during low frequency cycles, are those which yield optimal therapeutic activity. Such optimal therapeutic activity may correspond to the destruction of more than 1, 2, 5, 10, 10², 10³, 10⁵, 10¹⁰, or 10²⁰ cells, preferentially tumor cells, of virus, of bacteria, preferentially pathogenic bacteria, organs, tissues, vessels, the body part of the individual. Such destruction may in some cases be directly caused by heat, and in some other cases involve indirect mechanism such as the immune system.

In another embodiment of the invention, T_(max) and T_(min), preferentially reached during low frequency cycles, yield the lowest undesirable effects resulting from the treatment. This may correspond to the destruction of less than 1, 2, 5, 10, 10², 10³, 10⁵, 10¹⁰, or 10²⁰ healthy cells or to the absence of damage towards healthy cells.

In another embodiment of the invention, T_(max) and T_(min), preferentially reached during low frequency cycles, yield the highest anti-tumor efficacy with the lowest toxicity of the treatment.

In one embodiment of the invention, T_(max), preferentially reached during low frequency cycles, is larger than the physiological temperature by 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 50, 75, 100, 500, 10³, 10⁴, or 10⁵° C. T_(max) can be between 0 and 100° C., 20 and 75° C., 30 and 60° C., 37 and 50° C., 37 and 45° C., or between 37 and 41° C. In another embodiment of the invention, T_(min), preferentially reached during low frequency cycles, is above or below the physiological temperature by 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 50, 75, 100, 500, or 10³° C. T_(min) can be between 0 and 100° C., 20 and 75° C., 30 and 60° C., 37 and 50° C., 37 and 45° C., or between 37 and 41° C.

In one embodiment of the invention, the maximum temperature and/or the difference between the minimum and maximum temperatures, preferentially reached during low frequency cycles, favors an indirect mechanism of destruction of the infectious disease, preferentially the tumor, such as an immune mechanism. This may occur when maximum temperatures are moderate, preferably lower than 100, 80, 60, 55, 50, 45, or 43° C. This may also occur when the difference between minimum and maximum temperature is moderate, preferably lower than 100, 75, 50, 25, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1° C.

In another embodiment of the invention, the maximum temperature or the difference between maximum and minimum temperatures, preferentially reached during low frequency cycles, favors a direct thermal mechanism of destruction of the infectious disease, preferentially the tumor. This may occur when the maximum temperature is high, preferentially larger than 100, 80, 60, 50, 45, or 43° C. This may also occur when the differences between the minimum and maximum temperature is larger than 100, 75, 50, 25, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1° C.

In one embodiment of the invention, maximal and minimal temperatures are fixed before the beginning of the treatment depending on the body part of the individual, on its size, shape, composition, nature, and on the desired therapeutic effect.

The invention also concerns magnetic nanoparticles for use, for the prevention or treatment of a disease selected from a cancer, a tumor and an infection.

In one embodiment of the invention, the disease is selected from one of the disease mentioned in the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD), maintained by the World Health Organization.

In one embodiment of the invention, the disease is an infectious disease, such as a disease due to a proliferation of bacteria, preferentially pathogenic, of viruses, or of cells, preferentially tumor.

In one embodiment of the invention, the disease is a brain tumor, cervical cancer, colorectal cancer, cutaneous tumor, endometrial cancer, stomach cancer, liver cancer, gastrointestinal stromal tumor, malignant hemopathy, leukemia, multiple myeloma, lymphoma, Hodgkin's disease, non-Hodgkin's lymphoma, hepatocellular carcinoma, Kaposi's sarcoma, laryngeal cancer, mesothelioma, cancer of the esophagus, osteosarcoma, ovarian cancer, pancreatic cancer, skin cancer, oral cancer, lung cancer, small cell lung carcinoma, prostate cancer, rhabdomyosarcoma, kidney cancer, breast cancer, testicular cancer, thyroid cancer, soft tissue sarcoma, bladder carcinoma, myeloma (bone cancer), plasmacytoma, myeloma, germ cell cancer, neuroblastoma, osteosarcoma, retinoblastoma, cancer of the central nervous system, wilms tumor or nephroblastoma.

In one embodiment of the invention, the disease is associated with the condition of the individual or of the body part of the individual that is different from a normal condition. The disease can occur locally or on an entire organism or individual.

The invention also concerns a device comprising a generator of magnetic field or radiation oscillating at the high frequency and, medium and/or low frequency, and at least one magnetic nanoparticle.

In one embodiment of the invention, the magnetic field or radiation generator generates the magnetic field or radiation oscillating at the high frequency and, medium and/or low frequency.

In still another embodiment of the invention, the device is a medical device or a combination of several medical devices, or a drug, or a combination of several drugs, or a combination of at least a medical device and at least a drug, or at least a therapeutic substance.

The invention also concerns magnetic nanoparticles for use, wherein the application of a magnetic field or radiation oscillating at the high frequency and at the medium and/or low frequency, enables reaching a distance between the device generating the oscillating magnetic field or radiation and the body part of more than 50 cm.

In one embodiment of the invention, the distance between the device generating the oscillating magnetic field or radiation and the body part is larger than 1, 10, 20, 50, 75, 100, or 1000 cm.

The invention also relates to a device suitable for magnetic hyperthermia comprising a generator of magnetic field or radiation oscillating at a high frequency and at a medium frequency and/or low frequency.

In one embodiment of the invention, the device can represent any part or combination of parts of the device generating the oscillating magnetic field or radiation including the coil, the part or generator that generates or produces the alternating current, the part that is responsible for the generation of the alternating magnetic field or radiation, the cooling system, or the power supply.

In another embodiment of the invention, the magnetic nanoparticle represents the assembly of all nanoparticles, or of less than 90, 70, 50, 25, 10, or 1% of magnetic nanoparticles administered or comprised in the body part of the individual.

In one embodiment of the invention, the distance between the device and the magnetic nanoparticle is larger than 1, 10, or 100 nm, or 1, 10, or 100 μm, or 1, 10, or 100 mm, or 1, 10, or 100 cm, or 1, 10, or 100 m.

In another embodiment of the invention, the distance between the device and the magnetic nanoparticle is smaller than 1, 10, or 100 nm, or 1, 10, or 100 μm, or 1, 10, or 100 mm, or 1, 10, or 100 cm, or 1, 10, or 100 m.

In one embodiment, the generator of magnetic field or radiation is a generator of alternating current, where the alternating current is preferentially responsible for generating the oscillating magnetic field or radiation.

According to the invention, the device has a power larger than 10⁻⁶, 10⁻⁴, 10⁻², 1, 10, or 10³ Watt per cm³ of the body part.

In one embodiment of the invention, the current, preferentially the alternating current, produced by the device is larger than 1, 10, 50, 100, 500, or 1000 A.

In one embodiment of the invention, the current, preferentially the alternating current, produced by the device is smaller than 1, 10, 50, 100, 500, or 1000 A.

In another embodiment of the invention, the power, preferentially of the power supply of the device or of the device, is larger than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ KW.

In another embodiment of the invention, the power, preferentially of the power supply of the device or of the device, is smaller than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ KW.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the maximum or average magnetic field or radiation, generated by the device is lower than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ T.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the maximum or average magnetic field or radiation, generated by the device is higher than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ T.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the maximum or average magnetic field or radiation, generated by the device is smaller than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ T.

In still another embodiment of the invention, the strength or amplitude of the magnetic field or radiation, the maximum or average magnetic field or radiation, generated by the device is larger than 10⁻⁶, 10⁻⁴, 10⁻², 10⁻¹, 1, 10, 10², 10⁴, or 10⁶ T.

According to the invention, the magnetic field or radiation can preferentially be generated at a distance from the device of more or less than 1, 10, or 100 nm, or 1, 10, or 100 μm, or 1, 10, or 100 mm, or 1, 10, or 100 cm, or 1, 10, or 100 m, where the magnetic field or radiation can preferentially be generated within more or less than 10⁹, 10⁷, 10⁵, 10³, 10², 10, 1, 10⁻¹, 10⁻², 10⁻³, 10⁻⁵, 10⁻⁷, or 10⁻⁹ seconds.

In still another embodiment of the invention, the high, medium, and/or low frequency of oscillation generated by the device is smaller than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, 10⁸, or 10⁹ Hz.

In still another embodiment of the invention, the high, medium, and/or low frequency of oscillation generated by the device is larger than 10⁻⁹, 10⁻⁸, 10⁻⁷, 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, 10⁻², 10⁻¹, 1, 10, 10², 10³, 10⁴, 10⁵, 10⁶, 10⁷, 10⁸, or 10⁹ Hz.

In one embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and, medium and/or low frequency, enables to increase the distance between the device and the magnetic nanoparticle by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, compared with a system generating a magnetic oscillating only at high frequency.

In one embodiment of the invention, the device generating the magnetic field or radiation oscillating at high and medium frequency, enables to increase the distance between the device and the magnetic nanoparticle by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, compared with a system generating a magnetic oscillating only at high frequency.

In one embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and low frequency, enables to increase the distance between the device and the magnetic nanoparticle by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, compared with a system generating a magnetic field or radiation oscillating only at high frequency.

In one embodiment of the invention, when the distance between the device and the magnetic nanoparticles is increased by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, the percentage of nanoparticle, preferentially the body part of the individual, which is exposed to the oscillating magnetic field or radiation decreases by a factor of 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³.

In another embodiment of the invention, the magnetic field or radiation, oscillating at the high and, medium and/or low frequency, enables to reach a higher or larger maximum magnetic field or radiation and/or to reduce the diffusion of the magnetic nanoparticles outside the body part of the individual, compared with a magnetic field or radiation, oscillating only at the high frequency. It may therefore preferentially also lead to treatment and/or heating efficacy with less than 70, 50, 30, 20, 10, 5, 2, 1, or 0.1%, of magnetic nanoparticles, preferentially in the body part of the individual, exposed to the oscillating magnetic field or radiation, or with less than 70, 50, 30, 20, 10, 5, 2, 1, or 0.1% of the body part of the individual, preferentially comprising magnetic nanoparticles, exposed to the oscillating magnetic field or radiation.

The invention also concerns a device, where the high oscillation frequency is modulated by the medium oscillation frequency, wherein the modulation enables to reach a maximum magnetic field or radiation, which is larger than the maximum magnetic field or radiation reached without modulation.

In another embodiment of the invention, the device generating a high oscillation frequency modulated by a medium oscillation frequency, enables to reach a maximum magnetic field or radiation, which is 1.001, 1.01, 1.1, 1.2, 1.5, 2, 2.5, 3, 5, 7, 10, 15, 20, 25, 30, or 50 times larger or, which is 1, 2, 5, 10, 20, 30, or 50 mT higher or larger, than the maximum magnetic field or radiation reached without modulation.

In another embodiment of the invention, the device generating the high oscillating frequency modulated by a medium oscillation frequency, enables to reach an average magnetic field or radiation, which differs by less than 1, 2, 2, 5, 10, 25, 50, 75, 85, 95% from the average magnetic field or radiation, reached without modulation, where this percentage can correspond to [(H_(avwomod)−H_(avwmod))/H_(avwomod)], where H_(avwomod) and H_(avwmod) correspond to the average magnetic field or radiations without and with modulation, respectively.

In another embodiment of the invention, the use of a medium oscillation frequency enables to divide by a factor of 1, 2, 5, 10, 100, or 1000 the power of the generator necessary to produce the oscillating magnetic field or radiation, which can heat the magnetic nanoparticles. In another embodiment of the invention, the use of at least a high oscillating frequency and, a medium and/or a low oscillating frequency, enables the use of a generator, generating the alternating current, with a power lower than 200, 100, 50, 20, 10, 5, 2, or 1 kW to heat the nanoparticles.

This invention also concerns a device, such that the distance between a part of device generating the oscillating magnetic field or radiation and a body part to be treated by magnetic hyperthermia is of more than 50 cm.

In one embodiment, the part of the device generating the oscillating magnetic field or radiation is the part of the device in which the alternating current is circulating. In one embodiment of the invention, distance increase enables to improve treatment safety, since it preferentially leads to an increased distance between the individual or the body part of the individual and the device and minimizes risks of direct contact between the device and the individual or the body part of the individual.

In one embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and medium frequency, enables to increase the SAR of magnetic nanoparticles by a factor 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase this SAR by more than 0.1, 1, 5, 10, 50, 100, 500, or 1000 W/g_(Fe), compared to the SAR of magnetic nanoparticles measured by a system generating a magnetic field or radiation, oscillating only at high frequency.

In one embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and low frequency, enables to increase the SAR of magnetic nanoparticles by a factor 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase this SAR by more than 0.1, 1, 5, 10, 50, 100, 500, or 1000 W/g_(Fe), compared to the SAR of magnetic nanoparticles measured by a system generating a magnetic field or radiation, oscillating only at high frequency.

In one embodiment of the invention, the device generating a magnetic field or radiation oscillating at high, medium, and low frequency, enables to increase the SAR of magnetic nanoparticles by a factor 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase this SAR by more than 0.1, 1, 5, 10, 50, 100, 500, or 1000 W/g_(Fe), compared to the SAR of magnetic nanoparticles measured by a system generating a magnetic field or radiation, oscillating only at high frequency, or oscillating at high and medium frequency, or oscillating at high and low frequency.

In another embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and medium frequency enables to enhance treatment efficacy, i.e. to increase the number of pathological cells destroyed by the oscillating magnetic field or radiation, preferentially by a factor of more than 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase the number of destroyed pathological cells, preferentially by more than 1, 10, 10², 10³, 10⁶, 10⁹, 10¹², or 10¹⁵ cells, or to increase the percentage of the part of the body part of the individual, which is destroyed, preferentially by more than 1, 2, 5, 10, 25, 50, 75, 80, or 90%, compared with the number of pathological cells or the percentage of the body part of the individual, which is destroyed, by a magnetic field or radiation oscillating only at high frequency.

In one embodiment of the invention, the percentage of the body part of the individual, which is destroyed, represents the ratio between the volume of the body part of the individual, which is destroyed, preferentially measured after application of the oscillating magnetic field or radiation, and the total volume of the body part of the individual, preferentially measured after application of the oscillating magnetic field or radiation.

In another embodiment of the invention, the increase in the number of destroyed pathological cells or in the percentage of the body part of the individual, which is destroyed, corresponds to an increase in the number of apoptotic or necrotic cells, by more than 1, 10, 10³, 10⁶, or 10⁹, preferentially comprised in the body part of the individual.

In another embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and low frequency enables to enhance treatment efficacy, i.e. to increase the number of pathological cells destroyed by the oscillating magnetic field or radiation by a factor of more than 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase the number of destroyed pathological cells by more than 1, 10, 10², 10³, 10⁶, 10⁹, 10¹², or 10¹⁵ cells, or to increase the percentage of the body part of the individual, which is destroyed, by more than 1, 2, 5, 10, 25, 50, 75, 80, 90%, compared with the number of pathological cells or the percentage of the body part of the individual, which is destroyed, by a magnetic field or radiation oscillating only at high frequency.

In another embodiment of the invention, the device generating a magnetic field or radiation oscillating at high and medium frequency enables to enhance treatment efficacy, i.e. to increase the number of pathological cells destroyed by the oscillating magnetic field or radiation by a factor of more than 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase the number of destroyed pathological cells by more than 1, 10, 10², 10³, 10⁶, 10⁹, 10¹², or 10¹⁵ cells, or to increase the percentage of the body part of the individual, which is destroyed, by more than 1, 2, 5, 10, 25, 50, 75, 80, 90%, compared with the number of pathological cells or the percentage of the body part of the individual, which is destroyed, by a magnetic field or radiation oscillating only at high frequency.

In another embodiment of the invention, the device generating a magnetic field or radiation oscillating at high, medium and low frequency, enables to enhance treatment efficacy, i.e. to increase the number of pathological cells destroyed by the oscillating magnetic field or radiation by a factor of more than 1.001, 1.01, 1.1, 1.2, 1.5, 2, 3, 5, 10, 10², or 10³, or to increase the number of destroyed pathological cells by more than 1, 10, 10², 10³, 10⁶, 10⁹, 10¹², or 10¹⁵ cells, or to increase the percentage of the body part of the individual, which is destroyed, by more than 1, 2, 5, 10, 25, 50, 75, 80, or 90%, compared with the number of pathological cells or the percentage of the body part of the individual, which is destroyed, by a magnetic field or radiation oscillating only at high frequency, or oscillating at high and medium frequency, or oscillating at high and low frequency.

The invention also relates to magnetic nanoparticles for use in a hyperthermia method of therapeutic or prophylactic treatment or of diagnosis, wherein the magnetic nanoparticles are administered to the body part of the individual and the body part is exposed to a magnetic field or radiation oscillating at low and very low frequency.

In another embodiment of the invention, a hyperthermia method of therapeutic or prophylactic treatment or of diagnosis, is a method in which magnetic nanoparticles are exposed to a radiation oscillating at the low frequency. In this method, the exposure of magnetic nanoparticles to the magnetic field preferentially induces a temperature increase and/or a movement of the nanoparticles, which preferentially lead(s) to a specific interaction and/or transformation of body part of the individual. Such specific interaction and/or transformation can be the internalization or externalization of nanoparticles in/from cells, the death of cells, preferentially by apoptosis or necrosis, where these cells preferentially belong to the body part of the individual.

In one embodiment, magnetic hyperthermia is hyperthermia in the presence of nanoparticle or temperature increase of the body part comprising the nanoparticles, preferentially under the application of the radiation.

In some cases, hyperthermia can be magnetic hyperthermia.

The invention also relates to a method of hyperthermia therapeutic treatment, prophylactic treatment cosmetic treatment or diagnosis, comprising:

-   -   administering at least one magnetic nanoparticle to a body part         of an individual in need thereof; and     -   exposing the body part to an application of at least one heating         step and at least one cooling step,

wherein the combination of a heating step and a cooling step is a cycle,

wherein the cycle is repeated more than 2, 5, 10 or 10² times,

wherein the heating step comprises the application of a radiation on the body part or nanoparticle, which has a high frequency that is larger than 1, 10 or 100 kHz, and which is not an alternating magnetic field.

In some cases, the heating step can be the heating sequence.

In some other cases, the cooling step can be the cooling sequence.

In one embodiment of the invention, the radiation is not a magnetic field, preferentially a magnetic field of strength larger than 1 μT, 1 mT, 100 mT, 1 T or 10 T.

The invention also relates to a method of therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis of an individual in which magnetic particles are exposed to a radiation, comprising:

-   -   administering the magnetic nanoparticles to a body part of an         individual in need thereof; and     -   applying to the body part a radiation oscillating either:     -   (a) at a high frequency, at a medium frequency and at a low         frequency, or     -   (b) at a high frequency and at a lower frequency,

wherein the medium frequency applied in (a) is lower than the high frequency,

wherein the low frequency applied in (a) or (b) is lower than the high frequency, and the low frequency applied in (a) is lower than the medium frequency,

wherein applying the radiation at the low frequency in (a) or (b) is part of a repetition of at least one cycle of applying the radiation at the low frequency, and

wherein the at least one cycle of applying the radiation at the low frequency has at least one property selected in the group consisting of:

-   -   (i) the at least one cycle of applying the radiation at the low         frequency comprises a heating step in which the radiation at the         low frequency induces heating and a cooling step in which the         radiation at low frequency induces cooling, and     -   (ii) the at least one cycle of applying the radiation at the low         frequency comprises a step with increasing radiation strength at         the low frequency and a step with decreasing radiation strength         or zero radiation strength at the low frequency, and

wherein applying the radiation induces at least one of a temperature increase or a movement of the magnetic nanoparticles to cause internalization or externalization of the magnetic nanoparticles from cells or death of cells in the body part to provide the therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis,

wherein the radiation has a high frequency of oscillation that is characterized by the presence in the radiation of:

-   -   i) a frequency of oscillation that is larger than 1, 10 or 100         kHz, and/or     -   ii) a wavelength of oscillation that is lower than 10⁴, 10³,         10², 10 or 1 nm,

wherein the radiation is not an alternating or oscillating magnetic field of frequency larger than 1, 10 or 100 KHz.

In some cases, the radiation strength can be larger than 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ dose(s) of radiation (D), D/cm, D/cm², or D/cm³, Gry (Gray), Gry/cm, Gry/cm², or Gry/cm³, J(joule), J/cm, J/cm², or J/cm³, W(Watt) or W/cm, W/cm², or W/cm³ as preferentially measured per unit length, surface, or volume of nanoparticles or body part, as optionally measured per unit time such as second of application of the radiation.

In some cases, the dose of radiation is or represents the quantity of particles such as mass-less particles such as photons or massive particles such as protons, atoms, or atom parts irradiated on the body part or nanoparticle, preferentially during the treatment.

In some cases, the radiation strength can be smaller than 10²⁰, 10¹⁰, 10⁵, 10, 1, 0, 10⁻¹, 10⁻⁵, or 10⁻¹⁰ dose(s) of radiation (D), D/cm, D/cm², or D/cm³, Gry (Gray), Gry/cm, Gry/cm², or Gry/cm³, J(joule), J/cm, J/cm², or J/cm³, W(Watt) or W/cm, W/cm², or W/cm³ as preferentially measured per unit length, surface, or volume of nanoparticles or body part, as optionally measured per unit time such as second of application of the radiation.

In some cases, the radiation strength can be increased, preferentially during the heating step, preferentially by at least 10⁻²⁰, 10¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ dose(s) of radiation (D), D/cm, D/cm², or D/cm³, Gry (Gray), Gry/cm, Gry/cm², or Gry/cm³, J(joule), J/cm, J/cm², or J/cm³, W(Watt) or W/cm, W/cm², or W/cm³ as preferentially measured per unit length, surface, or volume of nanoparticles or body part, as optionally measured per unit time such as second of application of the radiation.

In some cases, the radiation strength can be decreased, preferentially during the cooling step, preferentially by at least 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ dose(s) of radiation (D), D/cm, D/cm², or D/cm³, Gry (Gray), Gry/cm, Gry/cm², or Gry/cm³, J(joule), J/cm, J/cm2, or J/cm³, W(Watt) or W/cm, W/cm², or W/cm³ as preferentially measured per unit length, surface, or volume of nanoparticles or body part, as optionally measured per unit time such as second of application of the radiation.

In some cases, the radiation, preferentially the oscillating radiation, has a frequency, preferentially a frequency of oscillation, preferentially a high, medium, and/or low frequency of oscillation.

In some cases, the frequency of oscillation of the radiation is larger than 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ Hz, kHz or MHz.

In some cases, the wavelength of oscillation of the radiation is larger than 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ nm.

In some cases, the frequency of oscillation of the radiation is smaller than 10²⁰, 10¹⁰, 10⁵, 10, 1, 0, 10⁻¹, 10⁻³, 10⁻⁵ or 10⁻¹⁰ Hz, kHz or MHz.

In some cases, the wavelength of oscillation of the radiation is smaller than 10²⁰, 10¹⁰, 10⁵, 10, 1, 0, 10⁻¹, 10⁻³, 10⁻⁵ or 10⁻¹⁰ nm.

In some cases, the radiation, preferentially the oscillating radiation, has a wavelength, preferentially a wavelength of oscillation, preferentially a high, medium, and/or low wavelength of oscillation.

In some cases, the high frequency of the radiation is or corresponds to or is proportional to the low wavelength of the radiation. This can be the case for light radiation.

In some other cases, the medium frequency of the radiation is or corresponds to or is proportional to the medium wavelength of the radiation. This can be the case for light radiation.

In some cases, the radiation frequency or wavelength can be decreased, preferentially during the cooling or heating step, preferentially by at least 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ Hz, kHz, MHz, or nm.

In some other cases, the radiation frequency or wavelength can be increased, preferentially during the cooling or heating step, preferentially by at least 10⁻²⁰, 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ Hz, kHz, MHz, or nm.

In still some other cases, the low frequency of the radiation is or corresponds to or is proportional to the high wavelength of the radiation. This can be the case for light radiation.

The invention also relates to the method according to the invention, wherein the radiation is selected in the group consisting of: i) an electric field, ii) laser light, iii) light produced by a lamp, iv) light emitted at a single wavelength, v) light emitted at multiple wavelengths, vi) a ionizing radiation, vii) microwave, viii) radiofrequency, ix) acoustic wave, x) infrasound, xi) sound, xii) ultra-sound, xiii) hyper-sound, and xi) alpha, beta, gamma, X-ray, neutron, proton, electron, ion, neutrino, muon, meson, photon particles or radiations.

The invention also relates to the method according to the invention, wherein the magnetic nanoparticles have a specific absorption rate (SAR) larger than 1 W/g.

The invention also relates to the method according to claim the invention, wherein the high frequency heats the magnetic nanoparticles or body part.

The invention also relates to the method according to the invention, wherein the low frequency is between 10⁻⁹ and 5.10⁵ Hz.

The invention also relates to the method according to the invention, wherein the heating step produces a temperature increase of more than 0.1, 1, 5 or 10° C. of the body part.

The invention also relates to the method according to the invention, wherein the heating step produces a temperature increase of less than 10⁵, 10³, 100, 10, 5, 2 or 1° C. of the body part.

The method according to the invention, wherein the cooling step induces a temperature decrease of more than 0, 1, 5 or 10° C. of the body part.

The invention also relates to the method according to the invention, wherein the cooling step produces a temperature decrease of less than 10⁵, 10³, 100, 10, 5, 2 or 1° C. of the body part.

In some cases, the magnitude of the temperature decrease of the body part can be lower than the magnitude of the temperature increase of the body part.

In some other cases, the magnitude of the temperature decrease of the body part can be larger than the magnitude of the temperature increase of the body part.

The invention also relates to the method according to the invention, wherein a compound is bound or linked to at least one magnetic nanoparticle before the radiation is applied, and the application of the radiation causes release of the compound from the at least one magnetic nanoparticle.

The invention also relates to the method according to the invention, wherein the at least one cycle of applying the radiation at a the low frequency comprises the heating step and the cooling step, and wherein: i) a maximum temperature and a minimum temperature is reached during the heating step and the cooling step, respectively, and ii) at least one parameter of the radiation that modulates temperature is set at a first value to reach the maximum temperature during the heating step and then the at least one parameter of the radiation is set at a second value to reach the minimum temperature during the cooling step, wherein the parameter of the radiation is preferentially the intensity, strength, power, frequency or wavelength of the radiation.

The invention also relates to the method according to the invention, wherein the method of therapeutic treatment, prophylactic treatment or cosmetic treatment or diagnosis is for of therapeutic treatment, prophylactic treatment cosmetic treatment or diagnosis of a disease selected from the group consisting of a cancer, a tumor, iron anemia disease, and an infection.

The invention also relates to the method according to the invention, wherein exposing the body part to the radiation is performed using a device generating the radiation located a distance of more than 0.1, 1, 5, 10 or 50 cm from the body part.

The invention also relates to the method according to the invention, wherein at least one first duration selected in the group consisting of: i) the duration of the heating step, ii) the duration of the cooling step, and iii) the time separating at least one heating step from at least one cooling step, is shorter than at least one second duration, which is the time of at least one session or the time that separates at least two sessions,

wherein a session is a succession of heating and cooling step(s),

wherein at least one heating step preferentially lasts for less than 1 minutes,

wherein at least one cooling step preferentially lasts for less than 1 minute,

wherein at least one session preferentially lasts for more than 5 minutes,

wherein at least two sessions are preferentially separated by more than 30 minutes.

In some cases, the at least one first duration and/or at least one second duration is/are longer than 10⁻⁵⁰, 10⁻³, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ second(s).

In some other cases, the at least one first duration and/or at least one second duration is/are shorter than 10⁵⁰, 10³, 10¹, 5, 2, 1, 0, 10⁻¹, 10⁻³, 10⁻⁵ or 10⁻¹⁰ second(s).

In some other cases, the at least one first duration is shorter than the at least one second duration by more than 10⁻⁵⁰, 10⁻³, 10⁻¹, 0, 1, 5, 10, 10³, 10⁵ or 10¹⁰ second(s).

In one embodiment of the invention, the method according to the invention comprises:

-   -   i) at least one heating step resulting from an increase in         physico-chemical disturbance;     -   and/or     -   ii) at least one cooling step resulting from a decrease in         physio-chemical disturbance;     -   and/or     -   iii) at least one cycle compriseing a step with increasing         physico-chemical disturbance and a step with decreasing         physico-chemical disturbance.

In one embodiment of the invention, the physico-chemical disturbance is associated with at least one of the following physico-chemical disturbance parameters:

-   -   (i) a movement of the magnetic nanoparticles, by more or less         than 1 nm, 10 nm, 100 nm, 1 μm, 10 μm, 100 μm, 1 mm, 10 mm, 1         cm, 10 cm or 1 m,     -   (ii) a release or a dissociation of a substance or compound from         the magnetic nanoparticle,     -   (iii) a change in a composition of the magnetic nanoparticle,     -   (iv) a variation in a pH of the nanoparticle by more or less         than 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 pH         unit(s),     -   (v) a variation in redox potential of the magnetic nanoparticle         by more or less than 1 V, 100, 10, 1, or 0.1 mV,     -   and/or     -   (vi) a variation in a feature surrounding the magnetic         nanoparticle selected from the consisting of pH, temperature,         redox potential, and chemical composition.

The invention also relates to the method according to the invention, wherein at least two magnetic nanoparticles are administered to a body part of an individual in need thereof, and the at least one or two magnetic nanoparticles has/have the property of being arranged or organized in a geometric figure selected in the group consisting of: a chain, segment, Balbis, Concave polygon, Constructible polygon, Convex polygon, Cyclic polygon, Equiangular polygon, Equilateral polygon, Penrose tile, Polyform, Regular polygon, Simple polygon, Tangential polygon, Polygons with specific numbers of sides, Henagon, Digon, Triangle, Acute triangle, Equilateral triangle, Heptagonal triangle, Isosceles triangle, Obtuse triangle, Rational triangle, Right triangle, Kepler triangle, Scalene triangle, Quadrilateral, Cyclic quadrilateral, Kite, Parallelogram, Rhombus, Lozenge, Rhomboid, Rectangle, Square, Tangential quadrilateral, Trapezoid, Isosceles trapezoid, Pentagon, Hexagon, Lemoine hexagon, Heptagon, Octagon, Nonagon, Decagon, Hendecagon, Dodecagon, Tridecagon, Tetradecagon, Pentadecagon, Hexadecagon, Heptadecagon, Octadecagon, Enneadecagon, Icosagon, Swastika, Star polygon, Pentagram—star polygon, Hexagram, Star of David, Heptagram, Octagram, Star of Lakshmi, Decagram—star polygon, Annulus, Arbelos, Circle, Archimedes' twin circles, Bankoff circle, Circumcircle, Disc, Incircle and excircles of a triangle, Nine-point circle, Circular sector, Circular segment, Crescent, Indalo, Lens, Lune, Reuleaux polygon, Reuleaux triangle, Salinon, Semicircle, Tomahawk, Triquetra, Heart, Archimedean spiral, Astroid, Cardioid, Deltoid, Ellipse, Heart, Heartagon, Various lemniscates, Oval, Cartesian oval, Cassini oval, Oval of Booth, Ovoid, Superellipse, Taijitu, Tomoe, and Magatama.

In some cases, the geometric can be present before and after administration of the magnetic nanoparticles to the body part and optionally application of the radiation.

In some other cases, the geometric can be present before administration of the magnetic nanoparticles to the body part and absent after administration of the magnetic nanoparticles to the body part and optionally application of the radiation.

In still some other cases, the geometric can be absent before administration of the magnetic nanoparticles to the body part and present after administration of the magnetic nanoparticles to the body part and optionally application of the radiation.

The invention also relates to the method according to the invention, wherein at least two magnetic nanoparticles are arranged in chain having at least one property selected in the group consisting of:

-   -   i) it has a length smaller than 10¹⁰, 10⁵, 10³ or 100 nm,     -   ii) the number of nanoparticles in each chain is smaller than         10⁵, 10³, 100, 50, 20, 10 or 5,     -   i) it has a length longer than 10⁻¹, 0, 1, 5, 10, 50, 100 or 10³         nm,     -   ii) the number of nanoparticles in each chain is larger than 2,         5, 10 or 10³,     -   iii) it increases the quantity of heat or compounds dissociated         from the nanoparticles under the application of radiation,     -   iv) it prevents aggregation and/or enables uniform nanoparticle         distribution,     -   v) the at least two nanoparticles in each chain are bound or         linked to each other,     -   vi) at least two crystallographic directions of at least two         adjacent nanoparticles comprised in at least one chain are         aligned, wherein such alignment is preferentially characterized         by an angle between the at least two crystallographic directions         that is lower than 90, 20, or 2° (degree).

The invention also relates to the method according to the invention, wherein the at least one magnetic nanoparticle is ferrimagnetic or ferromagnetic or has a ferrimagnetic or ferromagnetic behavior, wherein the ferromagnetic or ferrimagnetic behavior is preferentially observed at a temperature that is larger than 0, 0.1 or 1 Kelvin.

In some cases, the ferromagnetic or ferromagnetic behavior is associated with a non-zero coercivity or non-zero remanent magnetization.

In some cases, the ferrimagnetic or ferromagnetic nanoparticle has a coercivity larger than 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 2, 5, 10, 10³ or 10⁵ Oe.

In some cases, the ferrimagnetic or ferromagnetic nanoparticle has a coercivity smaller than 10¹⁰, 10⁵, 10, 5, 2, 1, 0, 10⁻¹, 10⁻³ or 10⁻⁵ Oe.

In some cases, the ferrimagnetic or ferromagnetic nanoparticle has a remanent magnetization larger than 10⁻¹⁰, 10⁻⁵, 10⁻¹, 0, 0.1, 0.5, or 0.9.

In some cases, the ferrimagnetic or ferromagnetic nanoparticle has a remanent magnetization smaller than 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.2, 0.1 or 0.

The invention also relates to the method according to the invention, wherein the at least one magnetic nanoparticle is synthesized by a living organism, preferentially a magnetotactic bacterium.

In some cases, the magnetotactic bacterium comprises a core and a coating, and the core and/or coating is synthesized by a living organism, preferentially a magnetotactic bacterium.

In some cases, the living organism can be a prokaryotic or eukaryotic cell, at least one cell, an individual, or an animal.

The invention also relates to the method according to the invention, wherein the at least one magnetic nanoparticle comprises at least a first metal, preferentially at least a first metal and at a second metal,

wherein the first metal is preferentially iron,

wherein the second metal is preferentially zinc or aluminum.

In some cases, the at least one first metal and/or the at least one second metal is/are selected in the group consisting of: actinide, actinium, aluminium, americium, antimony, argon, arsenic, astatine, barium, berkelium, beryllium, bismuth, bohrium, boron, bromine, caesium, calcium, californium, carbon, cerium, chlorine, chromium, cobalt, copernicum, cadmium, copper, curium, darmstadtium, dubnium, dysprosium, einsteinium, erbium, europium, fermium, fleovium, fluorine, francium, gadolinium, gallium, germanium, gold, hafnium, helium, hessium, holmium, hydrogen, indium, iodine, iridium, iron, krypton, lanthanide, lanthanum, lawrencium, lead, lithium, livermorium, lutetium, magnesium, manganese, meitherium, mendelevium, mercury, molybdenum, neodymium, neon, neptunium, nickel, niobium, nitrogen, nobelium, osmium, oxygen, palladium, phosphorus, platinum, plutonium, polonium, potassium, praseodymium, proctactinium, promethium, radium, radon, rhenium, rhodium, roentgenium, rubidium, ruthenium, rutherfordium, samarium, selenium, silicon, silver, sodium, strontium, sulphur, scandium, seaborgium, tellurium, terbium, thorium, thulium, tin, tantalum, technetium, thallium, titanium, tungsten, ununoctium, ununpentium, ununseptium, ununtrium, uranium, vanadium, xenon, ytterbium, yttrium, zinc, zirconium, and a combination of several of these chemical element(s).

The invention also relates to the method according to the invention, wherein the at least one magnetic nanoparticle has at least one property that exists or is observed before and/or after:

-   -   i) the administration of the at least one magnetic particle to         the body part of an individual in need thereof,     -   and/or     -   ii) the application of radiation on the at least one magnetic         nanoparticle or body part.

Tables

Table 1: Properties of the different coils used to generate the magnetic field, oscillating at the high, f_(h), and medium, f_(m), frequency for coils 1 to 5. These properties are measured at the center of each coil after 5 minutes of application of the magnetic field when the magnetic field is stabilized. The length and diameter of the different coils are indicated in cm, the strength of the alternating current within each coil is indicated in Ampere (A), the average and maximum magnetic fields, H_(av) and H_(max), measured at the center of each coil are indicated in mT, the ratio H_(max)/H_(av) is indicated, as well as the number of turns of each coil.

Table 2: Specific absorption rate (SAR), measured in Watt per gram of iron comprised in M-PLL or BNF-Starch, for suspensions of M-PLL or BF-Starch exposed during 650 seconds to a magnetic field oscillating at f_(h), f_(m), H_(max) and H_(av) values indicated in table 1 (centers of coils 1 to 5). The SAR is estimated using the relation SAR=(C_(eau)/X_(Fe))ΔT/δt, where C_(eau)=4.2 J.g⁻¹.K⁻¹ is the calorific capacity of water, X_(Fe)=0.01 g/mL is the iron concentration of the M-PLL or BNF-Starch suspension and ΔT/δt is the initial slope of the temperature variation with time of the M-PLL or BNF-Starch suspension, measured in ° C./sec. Increase in temperature, ΔT, after 650 seconds of the application of a magnetic field oscillating at f_(h) and f_(m) values, with H_(max) and H_(av) values indicated in table 1 (coils 1 to 5).

Table 3: Conditions of application of the oscillating magnetic field by coil 2, as a function of the distance from the edge of coil 2. The schematic diagram of FIG. 4(a) shows the two positions located at 5 cm (−5) and 8 cm (−8) from the edge of coil 2. For a distance from the edge of coil 2 of 5 cm, we have measured that f_(h)=192 kHz, H_(max)=13 mT, H_(av)=12 mT and H_(max)/H_(av)=1.1. For a distance from the edge of coil 2 of 8 cm, we have measured that f_(h)=189 kHz, H_(max)=5 mT, H_(av)=5 mT and H_(max)/H_(av)=1.1. The properties of the magnetic field are measured after magnetic field stabilization.

Table 4: Specific absorption rate (SAR) measured in Watt per gram of iron comprised in chemical nanoparticles (SIGMA, ref: 544884) for a suspension of chemical nanoparticles exposed during 650 seconds to a magnetic field oscillating at f_(h) and f_(m), with H_(max) and H_(av) values indicated in table 3 (coil 2). The SAR is estimated using the relation SAR=(C_(eau)/X_(Fe))ΔT/δt, where C_(eau)=4.2 J.g⁻¹.K⁻¹ is the calorific capacity of water, X_(Fe) is the iron concentration of the suspension of chemical nanoparticles in g/mL and δT/δt is the initial slope of the temperature variation with time of the suspension of chemical nanoparticles, measured in ° C./sec. Increase in temperature, δT, after 650 seconds of the application of a magnetic field oscillating at f_(h), f_(m), H_(max), and H_(av) values indicated in table 3 (coil 2). SAR and δT are measured for the tube containing chemical nanoparticles positioned at 5 and 8 cm from the edge of coil 2, with nanoparticle concentrations of 57, 87, 194, and 422 mg/mL in iron of nanoparticles.

Table 5: For GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, which are exposed to a magnetic field, oscillating at f_(h)=196 kHz, f_(m)=15 kHz, with H_(av)=61 mT and H_(max)=85 mT, applied during the heating times t₇ to reach 45° C. during the heating steps, and then not exposed to a magnetic field during the cooling times t₈ to reach 37° C. during the cooling steps (condition 4 of example 3). Heating and cooling steps are repeated 10 times. Values of t₇ and t₈, as well as H_(av), H_(max), and low frequencies, f_(l), deduced from low frequency sequences are estimated for the 10 cycles.

Table 6: For GL-261 cells brought into contact with 2 mg of BNF-Starch in 2 mL, which are exposed to a magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, with H_(av)=61 mT and H_(max)=85 mT, applied during the heating times t₇ to reach 50° C. during the heating steps, and then not exposed to a magnetic field during the cooling times t₈ to reach 37° C. during the cooling steps (condition 7 of example 3). Heating and cooling steps are repeated 6 times. Values of t₇ and t₈, as well as H_(av), H_(max), and low frequencies, f_(l), deduced from low frequency sequences are estimated for the 6 cycles.

Table 7: For GL-261 cells brought into contact with 2 mg of BNF-Starch, which are exposed to a magnetic field, oscillating field at f_(h)=196 kHz and f_(m)=15 kHz, with H_(av)=61 mT and H_(max)=85 mT, applied during the heating time t₇ to reach 55° C. during the heating steps, and then not exposed to a magnetic field during the cooling times t₈ to reach 37° C. during the cooling steps (condition 10 of example 3). Heating and cooling steps are repeated 4 times. Values of t₇ and t₈, as well as H_(av), H_(max), and low frequencies, f_(l), deduced from low frequency sequences are estimated for the 4 cycles.

Table 8: A suspension containing 25 μg in iron of BNF-Starch per mm³ of tumor is administered to subcutaneous glioblastoma GL-261 tumors of 60 to 90 mm³ and exposed to 21 hyperthermia sessions during which a magnetic field, oscillating at f_(h)=202 kHz and f_(m)=15 kHz, with H_(av)=27 mT and H_(max)=57 mT is first applied during a heating time t₇ to reach a temperature of 39-47° C. during the heating steps and then not applied during the cooling times t₈ to reach a temperature of 34-37° C. during the cooling times. During each of the 21 hyperthermia sessions, there are between 4 and 86 low frequency cycles. Values of t₇ and t₈, as well as H_(av), H_(max), and low frequencies, f_(l), deduced from low frequency sequences are estimated for the different cycles.

Table 9: A suspension containing 25 μg in iron of BNF-Starch per mm³ of tumor is administered to subcutaneous glioblastoma GL-261 tumors of 60 to 90 mm³ and exposed to 15 hyperthermia sessions during which a magnetic field, oscillating at f_(h)=202 kHz and f_(m)=15 kHz, with H_(av)=24-31 mT and H_(max)=54-67 mT is applied continuously during to reach a temperature of 37-47° C. during each hyperthermia session.

EXAMPLES Example 1 Application of a Magnetic Field, Oscillating at High and Medium Frequencies, f_(h) and f_(m), to Heat Nanoparticles

A volume of 100 μL of a suspension containing either nonpyrogenic magnetosomes coated with poly-L-lysine, also designated as central parts of magnetosomes coated with poly-L-lysine or magnetosome minerals coated with poly-L-lysine, (M-PLL) or BNF-Starch (Micromod, ref: 10-00-801) at a concentration of 10 mg/mL in iron was introduced into a 250 μL tube. The preparation, characterization and properties of M-PLL have been described in Patent PCT/FR2016/000095 which is incorporated herein by reference. The tube was placed at the center of each of the 5 induction coils, whose properties are summarized in table 1. Each coil was connected to a power source generating an alternating current of intensity varied between 73 and 682 A (Easy Heat 10 kW, Ambrell) to obtain the same H_(av), where the alternating current produced an oscillating magnetic field during 700 sec. The temperature variation inside the tube, following the application of the alternating magnetic field, was measured using a thermocouple (IT-18, Physitemp). The measurement of the alternating magnetic field was carried out using a magnetic probe placed at the center of each induction coil (Magnetic field probe, AMF life system), and an oscilloscope. The probe measured the variation with time of the axial voltage, U_(a), and of the radial voltage, U_(r). We deduced from U_(a) and U_(r) the variation of the magnetic flux density over time in the radial direction, H_(r)=U_(r)/[0.7f_(h)], and in the axial direction, H_(a)=U_(a)/[0.6f_(h)], where f_(h) is the high frequency of oscillation. We also deduced the variation of the magnitude of magnetic flux density with time using the relation: H=[(H_(a))²+(H_(r))²]^(1/2).

With the probe, we measured the variation of the magnetic flux density in the axial and radial directions, as well as the magnitude of the magnetic flux density, during 650 10⁻⁶ seconds, with a magnetic field measurement carried out every 0.16 10⁻⁶ seconds. The average and maximum magnetic fields, H_(av) and H_(max), were estimated, taking into accounts the maximum values of the amplitude of the magnetic field of each high frequency oscillation, H_(max,i), during a measurement time of 650 10⁻⁶ seconds.

For a magnetic field oscillating only at high frequency, the variation with time of the magnetic field amplitude is shown in FIG. 1(a), while for a magnetic field oscillating at high and medium frequency, the variation with time of the magnetic field amplitude is shown in FIG. 1(b). For coils 1 to 4, the medium frequency of f_(m)=15 kHz corresponds to a period T_(m)=1/f_(m)=67 10⁻⁶ seconds, which is much smaller than the measurement time and f_(m) can hence be measured for coils 1 to 4. For coil 5, the medium frequency f_(m)=2 kHz corresponds to a period T_(m)=1/f_(m)=500 10⁻⁶ seconds, which is also smaller than the measurement time and f_(m) can hence be measured for coil 5.

For coil 2, FIG. 2(a) shows the percentage of H_(max) and H_(av) reached as a function of time following the switching on of the device generating the oscillating magnetic field. It appears that 100% of H_(max) and H_(av), corresponding to a stable magnetic field, is reached 30 seconds after the device generating the oscillating magnetic field has been switched on. For the other coils (1, 3, 4), a stabilized magnetic field was also reached after 30 seconds and stabilization time was always observed to be below 30 seconds.

FIG. 2(b) shows the variation of the magnetic field amplitude as a function of time for a magnetic field oscillating at high, medium, and low frequency, with indications about A₇ and A₈ low frequency sequences. FIG. 2(c) shows the variation of the magnetic field amplitude as a function of time for a magnetic field oscillating at high and low frequency, with indications about A₉ and A₁₀ low frequency sequences.

FIGS. 3(a), 3(b), and 3(c), show variations with time of the magnetic flux density in the axial direction (FIG. 3(a)), the variation with time of the magnetic flux density in the radial direction (FIG. 3(b)), the variation with time of the magnitude of magnetic flux density (FIG. 3(d)), measured for coil 2.

For coils 1 to 5, magnetic fields oscillate at f_(h)=202 kHz (coil 1), f_(h)=195 kHz (coil 2), f_(h)=231 kHz (coil 3), f_(h)=329 kHz (coil 4), f_(h)=91 kHz (coil 5), and f_(m)=15 kHz (coils 1 to 4) or f_(m)=2 kHz (coil 5), where these frequencies are measured as described in FIGS. 1(a) and 1(b).

The maximum magnetic field, H_(max), corresponding to the maximum value of magnetic field amplitude among the different H_(max,i), H_(max)=_(i=1,n) ^(MAX H) _(max,i), where H_(max,i) is the maximum magnetic field amplitude of each high frequency oscillation and n is the number of oscillations considered in the measurement. H_(max) is equal to H_(max)=58 mT for an alternating current of intensity, I, of 190 A (coil 1), H_(max)=34 mT for I=195 A (coil 2), H_(max)=53 mT for I=73A (coil 3), H_(max)=56 mT for I=149A (coil 4), H_(max)=33 mT for I=682 A (coil 5) (table 1).

The average magnetic field, H_(av), which is estimated using the formula: H_(av)=(Σ_(i=1) ^(i=n) Hmax,i)/n, is H_(av)=26 mT for I=190 A (coil 1), H_(av)=25 mT for I=195A (coil 2), H_(av)=26 mT for I=73A (coil 3), H_(av)=24 mT for I=149A (coil 4), H_(av)=26 mT for I=682 A (table 1). In this experiment, we have used a value of the alternating current for each coil that yields similar average magnetic fields.

Coils 2 and 5 produce a ratio H_(max)/H_(av)=1.3-1.4, which is close to 1 (table 1).

Coils 1, 3, and 4, produce a higher or larger ratio H_(max)/H_(av) of 2-2.3 (table 1).

By using a double coil (coil 3) with a diameter about 2 times smaller than that of the single coil 1, the current required to reach a relatively similar high frequency f_(h) (f_(h)=231 kHz for coil 3 compared to f_(h)=202 kHz for coil 1), similar maximum and average magnetic fields, is 2.6 times lower (table 1).

For coil 4, the diameter and length are smaller than for coil 1, leading to a high oscillation frequency, which is higher or larger (329 kHz for coil 4 compared with 202 kHz for coil 1). Maximum and average fields are similar at 56-58 mT and 24-26 mT for coils 1 and 4 (table 1).

For coil 5, the diameter and length are significantly larger than for the other coils at 28 and 15 cm, respectively, and the medium and high oscillation frequencies are smaller at f_(m)=2 kHz and f_(h)=91 kHz (table 1).

Heating properties of M-PLL suspensions and BNF-Starch exposed to the oscillating magnetic fields generated by coils 1 to 5 for M-PLL and by coils 2 and 4 for BNF-Starch have also been studied. Variations of temperature with time of 100 μL of a M-PLL or BNF-Starch suspension at 10 mg/mL are presented in FIGS. 5(a) and 5(b) when these two suspensions are exposed to the alternating magnetic field generated by coil 2 (I=195 A, H_(max)=34 mT, H_(av)=25 mT) and coil 4 (I=149 A, H_(max)=56 mT, H_(av)=24 mT). The specific absorption rate, SAR, of M-PLL and BNF-Starch suspensions was measured, using the relationship: SAR=(C_(eau)/X_(Fe)) (ΔT/δt), where the SAR is measured in Watt per gram of iron, C_(eau)=4.2 J.g⁻¹.K⁻¹ is the calorific capacity of water, X_(Fe)=0.01g/mL is the iron concentration of the M-PLL or BNF-Starch suspension and ΔT/δt is the initial slope of the temperature variation with time, measured in ° C./sec. Temperature variation, indicated by ΔT, is calculated by subtracting: 1) the temperature reached by the M-PLL or BNF-Starch suspension after 650 seconds of application of the oscillating field by 2) the temperature measured before application of the oscillating magnetic field.

For M-PLL, the results of table 2 show that the induction coils which produce the highest SAR of 192-244 W/g_(Fe) and ΔT of 68-75° C., are coils 1, 3 and 4, which generate the oscillating magnetic field with the highest values of maximum magnetic field of 53-58 mT and highest value of H_(max)/H_(av) of 2-2.3. In contrast, the induction coils, which produce the lowest SAR of 6-84 W/g_(Fe) and ΔT of 5-57° C., are coils 2 and 5, which produce the lowest values of maximum magnetic field of 33-34 mT and H_(max)/H_(av) of 1.3-1.4. Furthermore, coil 5 which generates maximum and average magnetic field of 33 mT and 26 mT, respectively, similar to that of coil 2 of 34 mT and 35 mT, respectively, but has lower f_(h) and f_(m) values (f_(h)=91 kHz and f_(m)=2 kHz for coil 5 compared with f_(h)=195 kHz and f_(m)=15 kHz for coil 2), leading to SAR and ΔT, which are more than 10 to 14 times lower for coil 5 than those of coil 2 (table 2).

For BNF-Starch, the results of table 2 show that the induction coils which produce the highest SAR of 13 W/g_(Fe) and ΔT of 12° C., is coil 4, which generate the oscillating magnetic field with the highest values of maximum magnetic field of 56 mT and highest value of H_(max)/H_(av) of 2.3. In contrast, the induction coil, which produces the lowest SAR of 8 W/g_(Fe) and ΔT of 7° C. is coil 2, which produce the lowest values of maximum magnetic field of 34 mT and H_(max)/H_(av) of 1.4. Moreover, BNF-Starch produce much lower SAR and ΔT than the M-PLL, both for coils 2 and 4, which can be explained by their lower coercivity, H_(c) are 10 mT to BNF-starch and 6 mT for M-PLL, and lower ratio between remanent and saturating magnetization, M_(r)/M_(s) are equal to 0.19 for M-PLL and 0.15 for BNF starch.

We Can Conclude From This Example That:

i), Best heating properties, i.e. highest values of SAR and ΔT, are obtained for coils 1, 3 and 4, with the highest maximum magnetic field of 55±3 mT and the highest ratio H_(max)/H_(av) of 2-2.3, suggesting that the maximum magnetic field and/or H_(max)/H_(av) should be maximized in order to reach best nanoparticle heating properties under the application of an oscillating magnetic field.

ii), It is possible to obtain similar heating properties, i.e. similar values of SAR and ΔT, with similar values of H_(max)=55±3 mT and the highest ratio H_(max)/H_(av) of 2-2.3, (coils 1, 3, 4), suggesting that H_(max)=55±3 mT and H_(max)/H_(av) could be modified or adjusted to yield the desired heating properties.

iii), It is possible to obtain similar heating properties, i.e. similar values of SAR and ΔT, with coils of different diameters, coil number, and coil length (coils 1, 3, 4), suggesting that coil diameter, coil number, and coil length, could be modified or adjusted without necessarily modifying heating properties.

iv), For coils generating similar values of H_(max) and H_(max)/H_(av) (coils 2 and 5), better heating properties, i.e. higher or larger values of SAR and ΔT, are obtained for the coil with the highest f_(m) and f_(h) values (coil 2), suggesting that f_(m) and/or f_(h) should be maximized in order to reach best nanoparticle heating properties under the application of an oscillating magnetic field.

v) M-PLL lead to better heating properties than BNF-Starch both for coils 2 and 4, indicating that nanoparticle magnetic properties such as H_(c) and M_(r)/M_(s) should be maximized to reach best heating properties under the application of a magnetic field oscillating at high and medium frequency.

vi) The maximum and/or average magnetic field applied to heat M-PLL or BNF-Starch is larger than the coercivity of the nanoparticles (H_(c)=10 mT for BNF-Starch and H_(c)=6 mT for M-PLL at room temperature), which should enable rotation of the magnetic moment of the nanoparticles by application of the alternating magnetic field.

Example 2 Application of an Oscillating Magnetic Field to Heat Nanoparticle Suspensions Outside of the Coil

100 μL of a suspension containing uncoated iron oxide nanoparticles (SIGMA-ALDRICH, reference 544884) at different concentrations (422, 194, 87 and 57 mg/mL in iron) were introduced into a tube of 250 μL. The tube was then positioned at 5 cm and 8 cm from the edge of coil 2. The positions of the tube are indicated by −5 and −8 in the schematic diagram (FIG. 4(a). The tube was exposed to a magnetic field using the Ambrell Easy Heat LI 10 KW that generates an alternating current of 500 A for 1500 sec. The variation of temperature of the tube containing the nanoparticles was measured using a thermocouple (IT-18, Physitemp) while the properties of the magnetic field were measured using a magnetic probe (AMF life system) and an oscilloscope.

We measured the variation of the average, H_(av), and maximum, H_(max), magnetic field as a function of the distance from the edge of coil 2, designated as 0 in FIG. 4(a). FIG. 4(b) shows similar variations of H_(max) and H_(av) as a function of the distance from the center, 1.5 cm, of the coil. As can be seen in FIG. 4(b), the average and maximum magnetic fields decrease exponentially outside of coil 2, but are non-negligible up to 6 cm outside of the coils and could hence potentially be used to heat nanoparticles. Outside of the center of coil 2, the magnetic field appears to be “evanescent”, or is characterized by a magnitude or frequency of oscillation, preferably lower than those measured at the center or inside the coil (table 3).

Table 3 shows that the magnetic field oscillates at f_(h)=192 kHz at 5 cm from the edge of coil 2 and at f_(h)=189 kHz at 8 cm from the edge of coil 2. A medium frequency could not be detected for a measurement time of 650 10⁻⁶ seconds. In addition, the average and maximum magnetic fields are about two times lower at 8 cm from the edge of the coil (H_(av)=H_(max)=5 mT) than at 5 cm from the edge of the coil (H_(av)=H_(max)=12-13 mT), table 3.

The SAR and ΔT of chemical nanoparticles (SIGMA-ALDRICH, reference 544884) were estimated for a tube containing 100 μL of these nanoparticles, positioned at 8 cm and 5 cm from the edge of coil 2, and exposed to the magnetic field, oscillating at f_(h)=189-192 kHz with H_(max) and H_(av) indicated in table 3. When the tube containing the nanoparticles suspension was positioned at 8 cm from the edge of coil 2, table 4 indicates that SAR and ΔT values are low at 0.4-0.6 W/g_(Fe) and 1-8° C., respectively, which can be explained by the fact that the average and maximum magnetic fields are small at 5 mT (table 3). When the tube containing the nanoparticles suspension was positioned 5 cm from the edge of coil 2, SAR and ΔT values were higher or larger at 2-3 W/g_(Fe) and 13-45° C., respectively, explained by the fact that the maximum and average magnetic fields are larger at 12-13 mT, respectively (table 3).

It is therefore possible to heat a suspension of nanoparticles by positioning the tube containing a suspension of nanoparticles outside of coil 2, at 5 cm from the edge of this coil, by applying an oscillating magnetic field with maximum magnetic field larger than 10 mT.

Example 3 Application of a Magnetic Field Oscillating at a Low Frequency, f_(l), a Medium Frequency, f_(m), and a High Frequency, f_(h), for the Destruction of Tumor Cells In Vitro

Description of the various treatments: 500,000 GL-261 cells were seeded in petri dishes containing a culture medium composed of 1.6 ml of RPMI and 0.4 ml of calf serum. After incubation for 12 hours at 37° C. in the presence of 5% CO₂, the cells adhered to the surface of the Petri dishes and were confluent. For the application of the oscillating magnetic field, coil 2 was used.

The following 11 conditions of treatment were tested:

Condition 1: Confluent GL-261 cells were brought into contact with the culture medium and incubated at 37° C. for 12 hours.

Condition 2: Confluent GL-261 cells were brought into contact with the culture medium, exposed to a magnetic field, oscillating at high frequency f_(h)=196 kHz and medium frequency f_(m)=15 kHz, with H_(av)=61 mT and H_(max)=85 mT, applied continuously during 30 minutes.

Condition 3: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron and were then exposed to a magnetic field, oscillating at f_(h)=196 kHz and f_(m)=15 kHz, with average magnetic field varied between 49 and 61 mT and maximum magnetic field varied between 68 and 85 mT, to reach an average temperature of 45° C. during 30 minutes continuously.

Condition 4: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron and were then subjected to 10 cycles. During each cycle, a magnetic field, oscillating at a high frequency of 196 kHz, medium frequency 15 kHz, with an average magnetic field of 61 mT and maximum magnetic field of 85 mT, was applied, leading to a heating step up to 45° C., followed by the non-application of an alternating magnetic field, leading to a cooling step during which the temperature decreases from 45° C. down to 34-35° C. The times of heating and cooling steps, t₇ and t₈, as well as the low oscillation frequency, average and maximum magnetic fields deduced from t₇ and t₈ are indicated in table 5. The variations of temperatures with time during these low frequency cycles are indicated in FIG. 6(b), upper curve.

Condition 5: Confluent GL-261 cells were brought into contact with culture medium without BNF-Starch, were then exposed to the same 10 cycles as in condition 4 with the same magnetic field, t₇ and t₈ values. The variations of temperatures with time during the low frequency cycles are shown in FIG. 6(b), bottom curve.

Condition 6: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron, exposed to a magnetic field, oscillating at a high frequency of 196 kHz and medium frequency of 15 kHz, with an average magnetic field varied between 53 and 61 mT and a maximum magnetic field varied between 68 and 85 mT, to reach an average temperature of 50° C. continuously during 30 minutes.

Condition 7: Confluent GL-261 cells were brought into contact with culture medium and 2 mg in iron of BNF-Starch, were then exposed to 6 cycles. During each cycle, a magnetic field, oscillating at a high frequency of 196 kHz and medium frequency 15 kHz, with an average magnetic field of 61 mT and maximum magnetic field of 85 mT was applied, leading to a heating step up to 50° C., followed by the non-application of an alternating magnetic field to decrease the temperature from 50° C. down to 37° C. during a cooling step. The times of heating and cooling steps, t₇ and t₈, as well as the low oscillation frequency, average and maximum magnetic fields deduced from t₇ and t₈ are indicated in table 6. The variations of temperatures with time during these low frequency cycles are indicated in FIG. 6(c), upper curve.

Condition 8: Confluent GL-261 cells were brought into contact with culture medium without BNF-Starch and exposed to the same 6 cycles as in condition 7 with the same magnetic field and same time t₇ and t₈ as in condition 7. The variations of temperature with time during these low frequency cycles are shown in FIG. 6(c), bottom curve.

Condition 9: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron, exposed to a magnetic field oscillating at a high frequency of 196 kHz and medium frequency of 15 kHz, with an average magnetic field varied between 55 and 61 mT and a maximum magnetic field varied between 77 and 85 mT, to reach an average temperature of 55° C. continuously during 30 minutes.

Condition 10: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron, and were then exposed to 4 cycles. During each cycle, a magnetic field, oscillating at a high frequency of 196 kHz and medium frequency 15 kHz, with an average magnetic field of 61 mT and maximum magnetic field of 85 mT was applied, leading to a heating step at 55° C., followed by the non-application of an alternating magnetic field to decrease the temperature from 55° C. down to 37° C. during a cooling step. The times of heating and cooling steps, t₇ and t₈, as well as the low oscillation frequency, average and maximum magnetic fields deduced from t₇ and t₈ are indicated in table 7. The variations of temperatures with time during these low frequency cycles are indicated in FIG. 6(d), upper curve.

Condition 11: Confluent GL-261 cells were brought into contact without the BNF-Starch, and were then exposed to the same 4 cycles as in condition 10 with same magnetic field and same time t₇ and t₈ as in condition 10. The variations of temperature with time during these low frequency cycles are shown in FIG. 6(d), bottom curve.

Condition 12: Confluent GL-261 cells were brought into contact with culture medium and 2 mg of BNF-Starch in iron and incubated at 37° C. for 30 min.

After treatments, the culture medium was removed, cells were rinsed with PBS, PBS was replaced with culture medium and the cells were then incubated at 37° C. in the presence of 5% CO₂ for 12 hours. For each condition 1 to 12 of treatment, the percentage of dead cells, living cells, and the percentage of necrotic and apoptotic cells were measured. For that, the Petri dishes were rinsed with PBS, trypsin was added to detach cells, one milliliter of culture medium was added to the cells and the mixture was centrifuged at 1000 rpm for 10 minutes. The supernatant was removed and then replaced with 200 μl of PBS in order to obtain approximately 2.10⁶ cells per ml. 5 μl of Annexin V Alexa Fluoride and 1 μl of propidium iodide at 1 mg per ml were added to the cells. After 15 minutes, 800 μl of an Annexin 1× binding buffer solution were added to the cells and the fluorescence of the mixture was measured using a flow cytometer, which makes it possible to deduce the percentage of living cells, necrotic and apoptotic cells.

For condition 2, the temperature increased by 11° C. during the 30 minutes of continuous application of the oscillating magnetic field (FIG. 6(a)). For this condition, the percentage of living cells is 92%, similar to that of 97% obtained with the untreated cells (condition 1), indicating that continuous magnetic field application leading to continuous temperature increase of 11° C. does not induce significant cell death. For conditions 5, 8, and 11, the temperature increased, due to Eddy or Foucault currents, by 5° C. on average from 25° C. to 30° C. (condition 5, FIG. 6(b), bottom curve), by 4° C. on average from 27° C. to 31° C. (condition 8, FIG. 6(c), bottom curve), or 7° C. on average from 27° C. to 34° C. (condition 11, FIG. 6(d), bottom curve) during sequences of magnetic field application, and the temperature decreased by a relatively similar amount during sequences of non-application of the magnetic field. For these conditions, the percentage of living cells is 94%, similar to that of 97% obtained with the untreated cells (condition 1), indicating that Eddy or Foucault currents did not induce significant cell death.

For conditions 3 and 4, temperature either increased continuously during 30 minutes by 18° C. (condition 3, FIG. 6(a)) or increased by 20° C. and decreased by 10° C. during the first cycle, and increased by 10° C. and decreased by 10° C. during the remaining 9 cycles (condition 4, FIG. 6(b), upper curve). The percentage of living cells is 95% after continuous heating (condition 3) and 56% after sequential heating (condition 4), indicating that at this heating temperature of 45° C., the application of a magnetic field oscillating at a high, medium, and low frequency (condition 4) leads to enhanced toxicity towards cancer cells compared with a magnetic field oscillating at the high and medium frequency (condition 3).

For conditions 6 and 7, the temperature either increased continuously during 30 minutes by 23° C. (condition 6, FIG. 6(a)), or increased by 24° C. and decreased by 9° C. during a first cycle, and increased by 15° C. and decreased by 15° C. during the remaining 5 cycles (condition 7, FIG. 6(c), upper curve). The percentage of living cells is 91% after continuous heating (condition 6) and 0.4% after sequential conditions (condition 7), indicating that at this heating temperature of 50° C., the application of a magnetic field oscillating at high, medium, and low frequency (condition 7) leads to enhanced toxicity towards cancer cells compared with a magnetic field oscillating at the high and medium frequency (condition 6).

For conditions 9 and 10, the temperature increased continuously during 30 minutes by 28° C. (condition 9, FIG. 6(a)), or increased by 29° C. and decreased by 18° C. during the first cycle, and increased by 18° C. and decreased by 18° C. during the remaining 3 cycles (condition 10, FIG. 6(d), upper curve). The percentage of living cells is 2% after continuous heating (condition 9) and 1.6% under sequential conditions (condition 10), indicating that at this highest heating temperature of 55° C., application of magnetic fields oscillating at high, medium and low frequencies or at high and medium frequency, both lead to the destruction of most cancer cells.

For condition 12, temperature did not increase. The percentage of living cells is then 99%, indicating that the cytotoxic effect observed when nanoparticles are exposed to the oscillating magnetic field is due to the application of the magnetic field and not to nanoparticle toxicity.

We Can Conclude From This Example That:

The application of a magnetic field oscillating at high, medium, and low frequency, enables to strengthen treatment safety, i) to v), to enhance treatment efficacy, vi), and to use a method that does not necessitate to vary the magnetic field strength or frequency to reach a desired temperature during the heating steps.

i) In the absence of nanoparticles, cytotoxicity induced by the alternating magnetic field, in the presence of heat generated by Eddy or Foucault currents, is not observed.

ii) In the absence of nanoparticles, the application of a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz, and f_(l)=0.9-2.5 mHz, enables to heat sequentially, limiting the increase in temperature compared with the application of a field oscillating at f_(h)=195 kHz and f_(m)=15 kHz. Increase in temperature, due to Eddy or Foucault currents, is 11° C. under the application of a magnetic field oscillating at f_(h)=195 kHz and f_(m)=15 kHz compared to 6-8° C. under the application of a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz and f_(l)=0.9-2.5 mHz.

iii) For a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz and f_(l)=0.9-2.5 mHz, the average magnetic field is 31-44 mT, compared with 61 mT for a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz. It is therefore possible to decrease the average magnetic field by a factor of ˜1.4-2 by adding a low frequency and therefore decrease potential toxicity associated with the application of a too high average magnetic field.

iv) Temperatures of 44-45° C. are reached during 33 seconds using a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz, and f_(l)=1.6-2.5 mHz (FIG. 6(b)), whereas these temperatures are reached during 24 minutes using a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz (FIG. 6(a)). Temperatures of 49-50° C. are reached during 47 seconds using a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz, and f_(l)=1.2-1.7 mHz (FIG. 6(c)), whereas these temperatures are reached during 23 minutes using a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz (FIG. 6(a)). Temperatures of 52.5-53.5° C. are reached during 55 seconds using a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz, and f_(l)=0.9-1.1 mHz (FIG. 6(d)), whereas these temperatures are reached during 16 minutes using a magnetic field oscillating at f_(h)=195 kHz, f_(m)=15 kHz (FIG. 6(a)). Using a low oscillation frequency enables to decrease the time during which maximum temperature is achieved by a factor of 17 to 44, compared with the application of an oscillating magnetic field without the low frequency. This should enhance treatment safety and does not reduce the efficacy of cell destruction by the magnetic field.

v) The application of a magnetic field, oscillating at high, medium, and low frequency, enables to obtain a series of temperature gradient increase (+ΔT) followed by temperature gradient decrease (−ΔT). Temperatures of 44-45° C. were reached 10 times following ΔT of 8-20° C. followed by −ΔT of 8-10° C. by applying a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz, and f_(l)=1.6-2.5 mHz (FIG. 6(b)), whereas temperatures of 44-45° C. were reached only once following ΔT of 17-20° C. by applying a magnetic field, oscillating at f_(h)=195 kHz, f_(m)=15 kHz. Enhanced efficacy observed using the magnetic field oscillating at f_(h), f_(m), and f_(l), can be explained by the larger number of (+ΔT) and (−ΔT), compared with the magnetic field oscillating only at f_(h) and f_(m).

vi) When cancer cells are brought into contact with nanoparticles and heated to a temperature, which is below 55° C., the application of a magnetic field, oscillating at a high, medium, and low frequency leads to enhanced cytotoxicity compared with the application of a magnetic field, oscillating at high and medium frequencies.

vii) The application of a magnetic field enables a treatment where the number of sequences of magnetic field application, the number of sequences of non-application of the magnetic field, the average and maximum magnetic fields, the frequency of the applied magnetic field, the times of application and non-application of the magnetic field, are fixed at the beginning of the treatment depending on the temperature that one desires to reach. With this method, it is not necessary to vary the magnetic field strength or amplitude to reach a desired temperature during a sequence of magnetic field application. Moreover, once the cycles with associated heating and cooling times have been estimated, it is not necessary to measure the temperature during treatments. Cycles with defined heating and cooling times can be used for the treatment.

Example 4 Application of a Magnetic Field, Oscillating at a High Frequency of 196 kHz, Medium Frequency of 15 Hz, and Low Frequency of 4-25 mHz, for Efficient In Vivo Destruction of Tumors

Using a 1 mL 25 g syringe, a volume of 100 μl containing 10⁷ GL-261 murine glioblastoma cells was administered subcutaneously on the left flank, between the paw and the back of female mice black 6 C57BL/6J. The tumors grew during 10 to 15 days until they reached a size of 60 to 90 mm³. When the tumors reached this size, the mice were anesthetized with isoflurane gas and maintained at 37° C. by using heating plates. Using the same syringe, 50 μl of a suspension of BNF-starch nanoparticles at an iron concentration of 50 mg/mL were administered at the center of the tumors. The suspension of BNF-Starch was administered at a quantity of 25.t, measured in μg of iron comprised in nanoparticles, where t is the size of the treated tumors in mm³. Three different groups of mice were treated as follows:

A first group of 4 mice was exposed to 21 hyperthermia sessions, lasting 7 weeks with 3 sessions per week. Each session of hyperthermia consisted in 4 to 86 cycles (table 8). At the beginning of each cycle, to initiate the heating step, a magnetic field, oscillating at high and medium frequency, with f_(h)=195 kHz, f_(m)=15 kHz, H_(av)=27 mT and H_(max)=57 mT was switched on during a time t₇. As soon as the intra-tumor temperature reached 39.3-47.4° C., the oscillating magnetic field was stopped and the cooling step started to allow the intratumor temperature to decrease to 35-37.9° C. Cycles were repeated until a total exposure time of about 20 minutes was obtained for each hyperthermia session. The heating and cooling times, t₇ and t₈, measured during the different cycles of each hyperthermia session, as well as H_(av), H_(max), and f_(l), deduced from the values of t₇ and t₈ are indicated in table 8 and are average values among the 4 mice.

A second group of 10 mice was exposed to 15 hyperthermia sessions, lasting 5 weeks, with 3 sessions per week. Each session of hyperthermia consisted in 30 minutes of application of a magnetic field, oscillating at f_(h)=202 kHz, f_(m)=15 kHz, H_(av)=24-31 mT and H_(max)=54-67 mT to target an intratumor temperature of 37-48° C. For the first hyperthermia session, the targeted intratumor temperature was always reached while for subsequent hyperthermia sessions, it was not always possible to reach the targeted intratumor temperature and the average and maximum magnetic fields were then set at H_(av)=31 mT and H_(max)=67 mT, with f_(h)=202 kHz and f_(m)=15 kHz. For mice in which tumor volumes exceeded 150% of initial tumor sizes and targeted temperature of 43-46° C. was not reached, mice received a second intratumor nanoparticle administration of BNF-Starch at 25 μg in iron of nanoparticles per mm³ of tumor.

A third group of 10 mice was not treated further following BNF-Starch administration. In groups 1 and 2, the intra-tumor temperature was measured using an optical fiber positioned at the center of the tumors (Luxtron, LumaSense Technologies). In the groups, mice were euthanized when/if mouse weight had decreased by more than 20%.

For group 1, the heating and cooling times, t₇ and t₈, are presented as a function of the number of hyperthermia session in FIGS. 7(c) and 7(d). The heating time is observed to be relatively low and constant at 20 seconds during the 13 first hyperthermia sessions and then it strongly increases from 20 seconds to 320 seconds between the 13^(th) and 22^(nd) hyperthermia session, which may be due to BNF-Starch progressively leaving the tumor and/or being degraded following the 13^(th) hyperthermia session. A lower quantity of nanoparticles in the tumor would indeed require longer heating times to reach similar temperatures. By contrast, the cooling time remains relatively constant at 40 seconds, during the various hyperthermia sessions, suggesting that the cooling time does not depend on nanoparticle distribution and/or degradation. Instead, it may indeed depend on the environment of the nanoparticles such as type of tissue, organ, or blood irrigation of the tumor. The low frequency of oscillation is plotted as a function of number of hyperthermia session in FIG. 7(d). It is relatively constant and high at 16 10⁻³ Hz during the first 10 hyperthermia sessions and decreases down to 4 10⁻³ Hz between the 10^(th) and 22^(nd) hyperthermia session. This seems to indicate that to reach sufficiently high low frequency of oscillation, which may be necessary to reach antitumor activity, nanoparticle concentration should be sufficiently high and/or nanoparticles should not be degraded.

Length and width of the tumors, L and l, were measured in the different mice using a caliper every 2 days and the tumor volume was estimated using the formula; V_(tumoral)=0.5(L.l²). Average tumor volumes of the three groups of mice are plotted as a function of time following day 0 (the day of BNF-Starch administration) in FIG. 8(a). Average tumor volumes strongly increase for group 3 and mice are euthanized at day 16, suggesting the absence of antitumor activity in group 3 (FIGS. 8(a) and 8(b)). Average tumor volumes increase less significantly in group 2 than in group 3 (FIGS. 8(a)) and 20% of mice are still alive 245 days following BNF-Starch administration in group 2 (FIG. 8(b)), suggesting partial antitumor activity in group 2. Average tumor volumes decrease to zero at day 44 for group 1 and 100% of mice of group 1 are still alive 245 days following BNF-Starch administration (FIG. 8(b)), showing strong antitumor activity for group 1.

We Can Conclude From This Example That:

i) By heating magnetic nanoparticles comprised in tumors using a magnetic field oscillating at three frequencies (f_(h)=202 kHz, f_(m)=15 kHz, and f_(l)=4-25 mHz), it was possible to reach stronger antitumor efficacy than by using a magnetic field oscillating at two frequencies (f_(h)=202 kHz and f_(m)=15 kHz).

ii) When we used a magnetic field oscillating at three frequencies (f_(h)=202 kHz, f_(m)=15 kHz, and f_(l)=4-25 mHz), it was possible to reach strong antitumor efficacy without nanoparticle re-administration, whereas when we used a magnetic field oscillating at two frequencies (f_(h)=202 kHz and f_(m)=15 kHz), partial antitumor activity could only be reached when nanoparticles were re-administered. This suggests that the application of a magnetic field oscillating at three frequencies (f_(h)=202 kHz, f_(m)=15 kHz, and f_(l)=4-25 mHz) leads to nanoparticles being less degraded and/or leaving less rapidly the tumor than the application of a magnetic field oscillating at two frequencies (f_(h)=202 kHz and f_(m)=15 kHz).

iii) The heating time increases with the number of hyperthermia session and therefore seems to depend on nanoparticle concentration, whereas the cooling time remains relatively constant during the various hyperthermia sessions and therefore seems to be independent from nanoparticle concentration.

iv) The low frequency of oscillation is higher or larger during the first to 11^(th) hyperthermia sessions at 16 10⁻³ Hz than between the 16^(th) and 22^(nd) hyperthermia session, where f₁ is 4 10⁻³ Hz. This suggests that as the nanoparticle progressively leave the tumor and/or are degraded, f_(l) decreases.

TABLE 1 Properties of the different coils when magnetic field stabilized Measurement of f_(m), f_(h), H_(max) and H_(av) at the center of each coil f_(w) f_(h) Length Diameter I H_(max) H_(av) H_(max)/ Number of Coil (kHz) (kHz) (cm) (cm) (A) (mT) (mT) H_(av) turns 1 15 202 3.5 7 190 58 26 2.2 4 2 15 195 4 7 195 34 25 1.4 4 3 15 231 3.5 3 73 53 26 2.0 2 coils of four turn one in the other 4 15 329 2 3.5 149 56 24 2.3 3 5 2 91 15 28 682 33 26 1.3 3

TABLE 2 Magnetic heating properties (f_(n), f_(m), H_(max), H_(av), as indicated in table 1) M-PLL BNP Coll ΔT (° C.) S AR (W/g

) ΔT (° C.) S AR (W/g

) 1 71 244 2 57 84 7 8 3 68 202 4 75 192 12 13 5 5 6

indicates data missing or illegible when filed

TABLE 3 Conditions of magnetic field application when magnetic field stabilized Measurement of f_(m), f_(h), H_(max) and H_(av) at 5 cm and 8 cm from the edge of coil 2 Distance from the edge Current of the intensity f_(k) f_(w) coil H_(max) H_(av) H_(max)/ Coil (A) (kHz) (kHz) (cm) (mT) (mT) H_(av) 2 550 192 None 5 13 12 1.1 189 None 8 5 5 1.1

TABLE 4 SIGMA nanoparticles heating properties as a function of the distance from the edge of the coil 2 (

,

, H_(max), H_(av) as indicated in table 3) Concentration Distance from the in iron edge of the coil ΔT SAR (mg/ml) (cm) (° C.) (W/g

) 422 5 45 2 8 8 0.4 194 5 29 2 8 5 0.5 87 5 15 3 8 1 0.4 57 5 13 3 8 1 0.6

indicates data missing or illegible when filed

TABLE 5 Treatments of GL-261 cells brought into contact with 2 mg of chemical nanoparticles (BNF-Starch), exposed during

  to a magnetic field oscillating at

 196 kHz and

  15 kHz with H

 and

 61 mT to reach 45° C., followed by the non application of the magnetic field during

 (Coil 2)

 deduced from low frequency Time of Time of non- sequences application of the application of the (

 and

) magnetic field,

magnetic field,

H_(av) H_(max)

Cycle (heating steps) (cooling steps) (mT) (mT) (mHz) 1 7 minutes 23 secondes 2 minutes 57 secondes 44 85 1.61 2 3 minutes 31 secondes 3 minutes 23 secondes 31 85 2.42 3 3 minutes 21 secondes 3 minutes 17 secondes 31 85 2.51 4 3 minutes 30 secondes 3 minutes 9 secondes 32 85 2.51 5 3 minutes 27 secondes 3 minutes 25 secondes 31 85 2.43 6 3 minutes 34 secondes 3 minutes 10 secondes 32 85 2.48 7 3 minutes 35 secondes 3 minutes 6 secondes 33 85 2.49 8 3 minutes 40 secondes 3 minutes 30 secondes 31 85 2.33 9 3 minutes 45 secondes 3 minutes 36 secondes 31 85 2.27 10 3 minutes 42 secondes 3 minutes 36 seconder 31 85 2.28

indicates data missing or illegible when filed

TABLE 6 Treatments of GL-261 cells brought into contact with 2 mg of chemical nanoparticles (BNF-Starch), exposed during

 to a magnetic field oscillating at

 196 kHz and

 15 kHz with H

 and

 61 mT to reach 50° C. followed by the non application of the magnetic field during

 (Coil 2)

 deduced from low Time of Time of non- frequency sequences application of the application of the (

 and

) magnetic field,

magnetic field,

H_(av) H_(max)

Cycle (heating step) (cooling step) (mT) (mT) (mHz) 1 9 minutes 07 secondes 4 minutes 12 secondes 42 85 1.25 2 5 minutes 07 secondes 4 minutes 25 secondes 33 85 1.74 3 5 minutes 42 secondes 4 minutes 32 secondes 34 85 1.63 4 5 minutes 36 secondes 4 minutes 40 secondes 33 85 1.62 5 5 minutes 34 secondes 4 minutes 37 secondes 33 85 1.64 6 5 minutes 34 secondes 4 minutes 37 secondes 33 85 1.64

indicates data missing or illegible when filed

TABLE 7 Treatments of GL-261 cells brought into contact with 2 mg of chemical nanoparticles (BNF-Starch), exposed during

 to a magnetic field oscillating at

 196 kHz and

 15 kHz with H

 and

 61 mT to reach 55° C. followed by the non application of the magnetic field during

 (Coil 2)

 deduced from low Time of Time of non- frequency sequences application of the application of the (

 and

) magnetic field,

magnetic field,

H_(av) H_(max)

Cycle (heating step) (cooling step) (mT) (mT) (mHz) 1 11 minutes 56 secondes 5 minutes 54 secondes 41 85 0.93 2  8 minutes 49 secondes 5 minutes 49 secondes 37 85 1.14 3  8 minutes 40 secondes 5 minutes 50 secondes 36 85 1.15 4  9 minutes 15 secondes 5 minutes 23 secondes 39 85 1.14

indicates data missing or illegible when filed

TABLE 8 Treatments of GL-261 tumors of 60-80 mm³ by administration of 25 μg/mm³ in iron of BNF-Starch, followed by application of a magnetic field, oscillating at f_(h) = 202 kHz and f_(m) = 15 kHz with H_(max) = 57 mT and H_(av) = 27 mT during t₇ to a magnetic field oscillating to reach 45° C., followed by the non application of the magnetic field during t_(g). (Coil 1) Minimum Time of Maximum temperature application temperature Time of non- reached H_(av), H_(cox1), f_(j) deduced from of the reached application during low frequency sequences magnetic during of the magnetic cooling (t₇ and t_(g)) field, t₇ heating steps field, t_(g) steps H_(av) H_(max) f_(j) Hyperthermia Cycle (heating step) (° C.) (cooling step) (° C.) (mT) (mT) (mHz) 1 1 20 sec. 46.4-47.4 41 sec. 36.5-37.5 9 57 16 2 to 86 14 sec.  45-46.4 42 sec.  36-37.5 7 57 18 2 1 16 sec. 44.4-46  37 sec. 36.4-37.9 8 57 19 2 to 71 16 sec. 45.2-46.9 36 sec. 36.7-37.5 8 57 19 3 1 26 sec. 43.8-45.7 47 sec.  36-38.3 10 57 14 2 to 64 18 sec. 44.3-45.6 47 sec. 36.3-37.3 7 57 15 4 1 26 sec. 43.8-47.2 39 sec. 36.7-37.1 11 57 15 2 to 32 37 sec.  45-45.4 35 sec. 36.2-37.4 14 57 14 5 1 19 sec. 44.5-45.4 29 sec. 36.6-37.7 11 57 21 2 to 34 35 sec. 44.6-45.4 33 sec. 37.3-37.6 14 57 15 6 1 28 sec. 44.7-46  33 sec.  37-37.5 12 57 16 2 to 35 32 sec. 44.6-45.9 39 sec. 37.3-37.6 12 57 14 7 1 33 sec.  44-44.8 41 sec.  34-37.6 12 57 14 2 to 34 26 sec. 44.4-45.2 38 sec.  37-37.4 11 57 16 8 1 14 sec. 45.2-46.4 26 sec. 36.6-37.6 9 57 25 2 to 84 18 sec. 44.9-45.5 25 sec. 35.9-36.8 11 57 23 9 1 28 sec. 44.5-45.1 43 sec. 36.8-37.3 11 57 14 2 to 57 21 sec. 44.4-45.1 30 sec. 36.7-37.1 10 57 18 10 1 34 sec. 44.9-47  37 sec.  36-37.6 13 57 14 2 to 49 24 sec. 44.6-46.3 49 sec. 36.6-37  9 57 14 11 1 28 sec. 45.1-46  47 sec. 36.3-37.4 10 57 13 2 to 60 19 sec.  44-45.3 47 sec. 36.3-37.2 8 57 15 12 1 28 sec. 44.7-45.8 51 sec. 36.4-37.3 10 57 13 2 to 58 20 sec. 44.4-45.1 47 sec. 36.6-37.4 8 57 15 13 1 38 sec. 44.8-47  76 sec.  36-37.6 9 57 9 2 to 34 34 sec. 44.6-45.2 104 sec.  36.4-37.1 7 57 7 14 1 38 sec. 44.3-46.4 58 sec. 35.7-36.8 11 57 10 2 to 36 33 sec. 44.3-45  56 sec. 36.2-36.9 10 57 11 15 1 43 sec. 44.5-47  72 sec. 36.8-37.1 10 57 9 2 to 28 41 sec. 44.6-45  65 sec. 36.5-36.8 10 57 9 16 1 143 sec.  39.6-44.9 83 sec.  35-36.9 17 57 4 2 to 4 210 sec.  39.3-44.6 32 sec. 35.6-36.8 23 57 4 17 Same as cycle 16 18 19 20 21

TABLE 9 Treatments of GL-261 tumors of 60-80 mm³ by administration of 25 μg/mm³ in iron of BNP-Starch, followed by application of a magnetic field, oscillating at

 = 202 kHz and f_(m) = 15 kHz. (Coil 1) Maximum temperature Nano- reached during particules Hyper- heating steps adminin- H_(av) H_(max) thermia (° C.) istration (mT) (mT) 1 40-46   yes 24-31 54-67 2 32-46   no 25-27 54-57 3 31-48   no 25-27 54-57 4 31-47.8 yes 24-31 54-67 5 37-47.5 no 25-27 54-57 6 37-47.6 no 25-27 54-57 7 37-47.7 yes 24-31 54-67 8 37-47.8 no 25-27 54-57 9 37-47.9 no 25-27 54-57 10 37-47.1 no 25-27 54-57 11 37-47.1 no 25-27 54-57 12 37-47.1 no 25-27 54.57 13 37-47.1 no 25-27 54-57 14 37-47.1 no 25-27 54-57 15 37-47.1 no 25-27 54-57

indicates data missing or illegible when filed 

1. A method of therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis of an individual in which magnetic particles are exposed to a radiation, comprising: administering the magnetic nanoparticles to a body part of an individual in need thereof; and applying to the body part a radiation oscillating either: (a) at a high frequency, at a medium frequency, and at a low frequency, wherein the medium frequency is lower than the high frequency, and the lower frequency is lower than the high frequency and the medium frequency, or (b) at a high frequency and at a low frequency, wherein the low frequency is lower than the high frequency, wherein applying the radiation at the low frequency in (a) or (b) is part of a repetition of at least one cycle of applying the radiation at the low frequency, and wherein the at least one cycle of applying the radiation at the low frequency has at least one property selected in the group consisting of: (i) the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, and (ii) the at least one cycle of applying the radiation at the low frequency comprises a step with increasing radiation strength at the low frequency and a step with decreasing radiation strength at the low frequency, and wherein applying the radiation induces at least one of a temperature increase or a movement of the magnetic nanoparticles to cause internalization or externalization of the magnetic nanoparticles from cells or death of cells in the body part to provide the therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis, wherein the radiation has a high frequency of oscillation that is characterized by: i) a frequency of oscillation that is larger than 1, 10, or 100 kHz, and/or ii) a wavelength of oscillation that is lower than 10⁴, 10³, 10², 10, or 1 nm, wherein the radiation is not an alternating or oscillating magnetic field of frequency larger than 1, 10, or 100 KHz.
 2. The method according to claim 1, wherein the radiation is selected in the group consisting of: i) an electric field, ii)a laser light, iii) light produced by a lamp, iv) light emitted at a single wavelength, v) light emitted at multiple wavelengths, vi) ionizing radiation, vii) microwave radiation, viii)a radiofrequency, ix)an acoustic wave, x) an infrasound, xi) a sound, xii) an ultra-sound, xiii) a hyper-sound, and xi) alpha, beta, gamma, X-ray, neutron, proton, electron, ion, neutrino, muon, meson, photon particles or radiations.
 3. The method according to claim 1, wherein the magnetic nanoparticles have a specific absorption rate (SAR) larger than 1 W/g.
 4. The method according to claim 1, wherein the high frequency heats the magnetic nanoparticles or the body part.
 5. The method according to claim 1, wherein the low frequency is between 10⁻⁹ and 5×10⁵ Hz.
 6. The method according to claim 1, wherein the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, and the heating step produces a temperature increase of more than 1° C. of the body part.
 7. The method according to claim 1, wherein the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, and the cooling step induces a temperature decrease of more than 1° C. of the body part.
 8. The method according to claim 1, wherein a compound is bonded or linked to at least one magnetic nanoparticle before the radiation is applied, and the application of the radiation causes the release of the compound from the at least one magnetic nanoparticle.
 9. The method according to claim 1, wherein the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, and wherein: i) a maximum temperature and a minimum temperature is reached during the heating step and the cooling step, respectively, and ii) at least one parameter of the radiation that modulates temperature is set at a first value to reach the maximum temperature during the heating step and then the at least one parameter of the radiation is set at a second value to reach the minimum temperature during the cooling step, wherein the parameter of the radiation is an intensity, a strength, a power, a frequency or a wavelength of the radiation.
 10. The method according to claim 1, wherein the method of therapeutic treatment, prophylactic treatment or cosmetic treatment or diagnosis is for therapeutic treatment, prophylactic treatment, cosmetic treatment or diagnosis of a disease selected from the group consisting of a cancer, a tumor, iron anemia disease, and an infection.
 11. The method according to claim 1, wherein applying to the body part the radiation is performed using a device generating the radiation located a distance of more than 0.1, 1, 5, 10 or 50 cm from the body part.
 12. The method according to claim 1, wherein the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, wherein a session is a succession of at least one heating step and at least one cooling step, and the method comprises more than one session, wherein at least one heating step lasts for less than 1 minutes, wherein at least one cooling step lasts for less than 1 minute, wherein each session lasts for more than 5 minutes, and wherein at least two sessions are separated by more than 30 minutes.
 13. The method according to claim 1, wherein at least two magnetic nanoparticles are arranged in at least one chain having at least one property selected in the group consisting of: i) a length smaller than 2.10⁵ nm, ii) a number of magnetic nanoparticles in the at least one chain is smaller than 10³, i) a length longer than 10⁻¹ nm, ii) a number of magnetic nanoparticles in the at least one chain is larger than 2, iii) an increased quantity of heat or compounds dissociated from the magnetic nanoparticles under the application of radiation compared to a single magnetic nanoparticle, iv) aggregation prevention and/or uniform magnetic nanoparticle distribution, v) the at least two magnetic nanoparticles in the at least one chain are bound or linked to each other, viii) at least two crystallographic directions of at least two adjacent magnetic nanoparticles comprised in the at least one chain are aligned, wherein such alignment is characterized by an angle between the at least two crystallographic directions that is lower than 90, 20, or 2° (degree).
 14. The method according to claim 1, wherein the magnetic nanoparticles are ferrimagnetic or ferromagnetic or have a ferrimagnetic or ferromagnetic behavior, wherein the ferromagnetic or ferrimagnetic behavior is observed at a temperature that is larger than 0, 0.1 or 1 Kelvin.
 15. The method according to claim 1, wherein the magnetic nanoparticles are synthesized by a living organism.
 16. The method according to claim 1, wherein the at least one cycle of applying the radiation at the low frequency comprises a heating step in which the radiation at the low frequency induces heating and a cooling step in which the radiation at low frequency induces cooling, wherein: at least one heating step of at least one cycle results from an increase in physico-chemical disturbance; and/or at least one cooling step of at least one cycle results from a decrease in physio-chemical disturbance; and/or at least one cycle comprises a step with increasing physico-chemical disturbance and a step with decreasing physico-chemical disturbance.
 17. The method according to claim 16, wherein the physico-chemical disturbance is associated with at least one of the following physico-chemical disturbance parameters: (i), the application of the radiation oscillating at high frequency and, at medium and/or low frequency, (ii), a movement of the magnetic nanoparticles, by more or less than 1 nm, 10 nm, 100 nm, 1 μm, 10 μm, 100 μm, 1 mm, 10 mm, 1 cm, 10 cm or 1 m, (iii), a release or a dissociation of a substance or compound from at least one of the magnetic nanoparticles, to end up in the environment of the magnetic nanoparticles or body part, (iv), a change in a composition of at least one magnetic nanoparticle, inducing a loss of at least one metallic atom from the at least one magnetic nanoparticle, (v), a change in size of at least one magnetic nanoparticle, (vi), a variation in a pH of the magnetic nanoparticles, the environment of the magnetic nanoparticles, or the body part by more or less than 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 pH unit(s), (vii), a variation in redox potential of the magnetic nanoparticles, the environment of the magnetic nanoparticles, or the body part by more or less than 1 V, 100, 10, 1, or 0.1 mV, or (viii), a variation in a feature of the environment of the magnetic nanoparticles selected from the group consisting of pH, temperature, redox potential, and chemical composition of the environment. 